Doing Diatoms

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rnabholz
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Doing Diatoms

#1 Post by rnabholz » Sat May 14, 2016 9:49 pm

Over the winter I had been thinking about things that I wanted to investigate once the warmer weather finally came around. One thing that had intrigued me was Diatoms. Kurt was pretty active in gathering, cleaning and mounting diatoms and he had suggested that I should consider doing the same. He referred me to three YouTube videos that really made it seem accessible and relatively easy.

Part One of three is here:



I did some additional reading and researching had basically decided to move forward when Kurt sent me a few of his slides, and that sealed the deal. I had to give it a try.

The videos showed the use of a couple pieces of equipment that I did not have, but seemed to be very helpful, a centrifuge and hot plate.

The centrifuge shown was a hand cranked unit. I was able to find those on Ebay and Amazon, but they were around 50 to 75 bucks. Just for fun I checked Ebay for electric units, and sure enough found some very affordable used units and even some new Chinese units for about $60. I decided on a used Hamilton Bell Angle Centrifuge, that included 20 tubes and a home made wooden test tube rack. It arrived and was great operational and cosmetic shape. Quite a bargain I think.
Diatoms Centrifuge.jpg
Diatoms Centrifuge.jpg (78.57 KiB) Viewed 10334 times
A similar story on the hotplate. Another used unit, a Corning model that looked to be quite dirty in the auction pictures, but I suspected it could be cleaned up. In the end the dirty pictures helped me get it for a song, and with some elbow grease, cleaned up nicely.
Diaton HotPlate.jpg
Diaton HotPlate.jpg (79.38 KiB) Viewed 10334 times
So with the basic infrastructure laid in, there was only one thing left to do – go get some diatoms.

I put together a kit for the outing, a small bin for washing the rocks in, some fresh water, a brush, some sample collection bottles and a turkey baster to gather the goods from the bottom of the tray – ready to go.
Diatom Kit.jpg
Diatom Kit.jpg (94.52 KiB) Viewed 10334 times
I selected three locations for my first gathering mission. The Wapsipinicon River flows through my home town, making its way from southern Minnesota, through eastern Iowa, ultimately joining the mighty Mississippi river. In my town, the river is dammed, originally for a Feed Mill. The dam forms an impoundment, and it was ¼ mile from the dam that I gathered my first sample. Walking the shore, I spotted a prime looking football sized rock, covered with a brown sludge looking material. I used a hand rake to drag it to shore where I could grab it.
Diatom Rock 1.jpg
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Placed in the bin, I used the brush to scrub the material free of the rock, and the water to wash it into the bottom of the bin. Where it was collected by the turkey baster and placed into a sample jar.

I did the same, upriver about 6 miles on a section of the same river that moved more quickly than at the impoundment.

The last spot was at a county park, It too was an impoundment above a dam on a creek that formed a small lake known as Fontana Lake just outside of Hazleton Iowa.

Back home with the treasured goods, the first question was “Do I have any Diatoms?” A quick slide for each sample was thrown together and viewed – Bingo! All three samples showed a tremendous amount of Diatoms. Of particular interest was the difference in the samples. The two from the different portions of the river showed a very similar mix of varieties. The sample from Fontana showed a significantly increased number of varieties, there was a clear difference in the populations.

On to the cleaning step. The videos described a simple process of cleaning the diatoms using drain cleaner. While drain cleaner must be handled with care, it is much less intimidating that some of the other methods that I had read about using Hydrochloric or Sulfuric Acid. Kurt had also advised that the had good luck with Liquid Plumr.
Diatom PreCleaner.jpg
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Three tubes, one for a sample from each gathering spot were prepared and the drain cleaner was added. There was bubbling, a good sign something was happening. According to the video, after a short while we should see some very clean, white frustules gathered at the bottom of the tube.

Not so much….

Continued...
Last edited by rnabholz on Sun May 15, 2016 5:53 pm, edited 3 times in total.

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Re: Doing Diatoms

#2 Post by rnabholz » Sat May 14, 2016 9:59 pm

For the next week, I rinsed, replaced the drain cleaner, agitated, rinsed, replaced… and my sample never came anywhere near looking nice and clean. Further, samples taken from the batches and viewed under the scope showed that there was still a lot of cleaning left to do.

What next – Some reading found some folks extolling the virtues of food grade 35% Hydrogen Peroxide as a cleaning agent. I ordered some, and after a careful rinsing of the samples, deployed it.

I could see that the samples were getting lighter in color, but after a couple days of rinsing and repeating there did not seem to be any further progress being made.

I pulled a sample, and found that things were cleaner, but another thing was also obvious. The samples were significantly damaged. Most of the long forms were broken, many of the forms that I had seen before the treatment seem to be missing. In general, it looked like they had been beaten, battered and dissolved. No wonder- 10 days of chemicals and agitation.

Back to square one.

I was encouraged by the progress the Hydrogen Peroxide made with the samples and decided to try that as the main agent. Using a process I had read about, I prepared some samples, added HP and let it sit overnight. The next night I rinsed the samples, added fresh HP and placed the tubes in a warm water bath – around 200 degrees F for three hours.

At the end of that time, I removed them from the bath, and added a very small bit of Potassium Dichromate – there was a very energetic reaction that continued for about 30 minutes. When things had subsided, I rinsed the samples and took a look at a sample with the Microscope.

Eureka! Clean as a whistle, and all forms were present and intact.

While waiting on the cleaning process, I had placed an order for my mounting agent, Pleurax. Compared to some other agents, I liked the fact that it was solvent in Isopropyl Alcohol. Some of the others used Toulene or Xylene – both much nastier chemicals. I placed the order and it arrived about 10 days later from the Netherlands.

Using the process that I saw demonstrated on the Videos, I placed coverslips on the hotplate, on which I placed a couple of drops of the sample that I had agitated to suspend the diatoms in the mix. I then slowly and gently heated the slips to dry the water and fix the diatoms to the underside of the slip.

Placing a small drop of the Pluerax on a slide, the slip is placed, Diatom side down onto the Pleurax and slide.

The entire slide is them placed on the hotplate and gradually warmed to about 350 degrees F and “cooked” for 15 minutes. During that time you will see bubbles form and escape from under the coverslip, sometimes in what seems to be a pretty violent action, that is normal. It should not spatter – if you see that happening, reduce the heat some.



The bubbles slowly begin to subside and at the end of the 15 minutes are mostly gone. I removed it from the heat to a safe surface, and used the end of my tweezers to apply light pressure on the coverslip to force out any remaining bubbles – there were few, the Pleurax settles nicely once removed from the heat.

Once cooled, I carried them over to the scope for a long anticipated first look.

Diatoms everywhere – every shape and size, all presented clearly and sharply! Success!

My first slides were a bit dense – lots of diatoms, probably too many, and they do show a bit too much mineral content for my taste, but both of those can be addressed by diluting the sample a bit more before placing it on the slide. My later slides do show some improvement, but this piece is clearly where experience will help and is defininely where the “art” comes in.

I been too busy to shoot many images yet, but have enjoyed some viewing sessions, including using the 100x objective. The slides hold up excellently to the magnification, and so should make great photographic subjects.

Here are a few Afocal "Snapshots" not fine art, but will give you an idea of what I am seeing.
Diatom View 1.jpg
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Diatom View 3.jpg
Diatom View 3.jpg (176.26 KiB) Viewed 10333 times
Diatom View 5.jpg
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Diatom View 6.jpg
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Diatom View 7.jpg
Diatom View 7.jpg (155.88 KiB) Viewed 10333 times
Last edited by rnabholz on Mon May 16, 2016 3:12 pm, edited 4 times in total.

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Re: Doing Diatoms

#3 Post by rnabholz » Sat May 14, 2016 10:02 pm

Diatom View 2.jpg
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Diatom View 4.jpg
Diatom View 4.jpg (87.94 KiB) Viewed 10333 times
I will be doing some more serious photographic work on these as time goes on.

In all it is an exciting start in this new endeavor. I am looking forward to gathering more samples and exploring all of what the world of Diatoms have to offer.

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Re: Doing Diatoms

#4 Post by rnabholz » Sat May 14, 2016 10:25 pm

A few more pictures from the process

Centrifuge Loaded
Diatoms Centrifuge Loaded.jpg
Diatoms Centrifuge Loaded.jpg (103.42 KiB) Viewed 10330 times
Diatoms Not Clean
Diaton Not Clean.jpg
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Diatoms in Water Bath
Diatom Water Bath.jpg
Diatom Water Bath.jpg (84.77 KiB) Viewed 10330 times
Slide Template
Diatom Template.jpg
Diatom Template.jpg (64.8 KiB) Viewed 10330 times
Monitoring the increase to the curing temperature
Diatom Temp.jpg
Diatom Temp.jpg (67.08 KiB) Viewed 10330 times

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Re: Doing Diatoms

#5 Post by billben74 » Sat May 14, 2016 11:26 pm

What a fantastic post. :)

At some point I will look your post back up and have a go.
Lovely initials results. Lots of fantastic looking diatoms.

You must be chuffed to bits.
Good effort and congratulations on getting going on an impressive endeavour.

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Re: Doing Diatoms

#6 Post by zzffnn » Sat May 14, 2016 11:46 pm

Rod,

I very much enjoy your story and reading about your experiments and results!

I think the sand/mineral particles are heavier (more dense) than diatoms and should sink to the very bottom of centrifuge tubes. Diatoms layer should stay above sands, if you spin fast enough. At least, that would happen in research lab centrifuges.

So I would suggest not taking the very bottom layer and use a narrow bottom centrifuge tube, if you have that option.

And you can do several rounds of wash-centrifugation to remove sands too. Basically, you trade quantity with clearness (and get less but cleaner samples).

What concentration of sulfuric acid was recommended? If it is much lower than 90% and handled carefully, it should not be too dangerous (safer than the evaporation of HCL). But your preferred method seemed to work well anyway.

And for other microscopists:

For diatoms, you don't have to have a sophisticated centrifuge. More expensive ones can spin at precise slower speed (say 200 rpm), which is a safer speed for delicate ciliates. Diatoms, having rigid skeletons, can be centrifuged at high speed without getting damaged. Cheaper small centrifuges spin at pretty high speed of thousands rounds per minutes (rpm).

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Re: Doing Diatoms

#7 Post by rnabholz » Sun May 15, 2016 12:42 am

billben74 wrote:What a fantastic post. :)

At some point I will look your post back up and have a go.
Lovely initials results. Lots of fantastic looking diatoms.

You must be chuffed to bits.
Good effort and congratulations on getting going on an impressive endeavour.

Thanks billben

I am very pleased, but admit was a bit frustrated at the slow progress in the beginning of the cleaning phase. Not sure what was different with my samples than those that had such good luck with the drain cleaner, but all is well that ends well.

Hope you do have a go at it. The views are worth the effort.

Rod
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Re: Doing Diatoms

#8 Post by rnabholz » Sun May 15, 2016 1:01 am

zzffnn wrote:Rod,

I very much enjoy your story and reading about your experiments and results!

I think the sand/mineral particles are heavier (more dense) than diatoms and should sink to the very bottom of centrifuge tubes. Diatoms layer should stay above sands, if you spin fast enough. At least, that would happen in research lab centrifuges.

So I would suggest not taking the very bottom layer and use a narrow bottom centrifuge tube, if you have that option.

And you can do several rounds of wash-centrifugation to remove sands too. Basically, you trade quantity with clearness (and get less but cleaner samples).

What concentration of sulfuric acid was recommended? If it is much lower than 90% and handled carefully, it should not be too dangerous (safer than the evaporation of HCL). But your preferred method seemed to work well anyway.

And for other microscopists:

For diatoms, you don't have to have a sophisticated centrifuge. More expensive ones can spin at precise slower speed (say 200 rpm), which is a safer speed for delicate ciliates. Diatoms, having rigid skeletons, can be centrifuged at high speed without getting damaged. Cheaper small centrifuges spin at pretty high speed of thousands rounds per minutes (rpm).
Thanks zz, glad you liked it.

My tubes do have the tapered bottom. I did notice the sand gathering at the bottom, but not knowing just how much diatom material I had, was reluctant to throw anything out.

I did employ a technique when taking the sample to agitate to suspend the material, and then wait 30 second before drawing. Hopefully letting the heavier sands settle, and drawing from the top of the column.

For the future, I will feel more confident about "skimming" the top layer, as in the end it doesn't take a great deal of material to make a lot of slides.

The centrifuge tops out at 3600 rpm, plenty effective for my purposes, and as I said, seemed to separate things nicely.

Regarding the acid, handling is only part of the concern, fumes are the other. Without a fume hood, and the processes calling for heating, I really don't want to expose the household to the nastiness that results. As you say, HP seems to work, so until that changes, I think I am set.

Thanks for the interest and info.

Rod

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Re: Doing Diatoms

#9 Post by zzffnn » Sun May 15, 2016 1:22 am

Sounds good, Rod.

You could also scrape the rock less and more gently to avoid removing mineral particles, if you have not already done it. As you said, since you had lots of diatoms in the end, you could trade quantity for clearness.

H2SO4 should not make fume, unless its final concentration goes above 85% or so. But it may dissolve diatom skeletons more, if not controlled well. I don't blame you for not liking it.

You may try white vinegar too, if it does not react with other chemicals that you use. H2O2 will not react with vinegar - they should enhance each other's effect. You may not need vinegar though, if it already work well as it is.

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Re: Doing Diatoms

#10 Post by KurtM » Sun May 15, 2016 3:36 am

rnabholz wrote:...and added a very small bit of Potassium Dichromate – there was a very energetic reaction...
What is Potassium Dichromate?
zzffnn wrote:H2SO4
And what's that?

Most excellent post, Rod! I'm also very impressed with your variety of forms, will have to see about sweet talking you into sending me some of it, or just trading slides? This is making me anxious to get home and back into diatom cleaning and slide making.

Wonder how muriatic acid might work - Fan, you have any ideas?
Cheers,
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Re: Doing Diatoms

#11 Post by zzffnn » Sun May 15, 2016 3:50 am

Kurt,

sulfuric acid = H2SO4

I don't have any experience with muriatic acid. I can only Google it and report back, if you need.

I am curious about Potassium Dichromate too.

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Re: Doing Diatoms

#12 Post by rnabholz » Sun May 15, 2016 5:03 am

zzffnn wrote:Sounds good, Rod.

You could also scrape the rock less and more gently to avoid removing mineral particles, if you have not already done it. As you said, since you had lots of diatoms in the end, you could trade quantity for clearness.

H2SO4 should not make fume, unless its final concentration goes above 85% or so. But it may dissolve diatom skeletons more, if not controlled well. I don't blame you for not liking it.

You may try white vinegar too, if it does not react with other chemicals that you use. H2O2 will not react with vinegar - they should enhance each other's effect. You may not need vinegar though, if it already work well as it is.
Thanks zz

I am not sure that the mineral is coming solely from the rock.

Like many rivers in Iowa, the Wapsi carries a good deal of silt. I would not be surprised in the least if it was just deposited on the surface. The flow of the river can at times be fairly slow, especially in the impoundment, and silt would be more likely to settle out.

I'll file away the white vinegar suggestion. At this time, I think I have a recipe that will do the job, but who knows what the next batch will bring.

Thanks again

Rod

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Re: Doing Diatoms

#13 Post by rnabholz » Sun May 15, 2016 5:15 am

KurtM wrote:
rnabholz wrote:...and added a very small bit of Potassium Dichromate – there was a very energetic reaction...
What is Potassium Dichromate?
zzffnn wrote:H2SO4
And what's that?

Most excellent post, Rod! I'm also very impressed with your variety of forms, will have to see about sweet talking you into sending me some of it, or just trading slides? This is making me anxious to get home and back into diatom cleaning and slide making.

Wonder how muriatic acid might work - Fan, you have any ideas?

Hey Kurt,

When it comes to chemistry, I am a trained monkey with a PayPal account, just tell me what to order and consider it done. Other than knowing it is an oxidizer I can't help you much.

A search turned up some good info, apparently also known as Potassium Bichromate if you need another search term.

Bright orange, granular. I found a source on Ebay.

Not knowing what to expect, I added the equivalent of about a third of a baby aspirin to 50ml of diatoms and warm HP, and the 150ml tube barely held the reaction. S.L.O.W. and easy with this combo.

As far as trading slides or material, I am already behind with you so you know I will be happy to ship you whatever you want. Anytime.

Thanks for your encouragement and guidance.

Rod

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Re: Doing Diatoms

#14 Post by zzffnn » Sun May 15, 2016 2:11 pm

Hydrochloric acid = muriatic acid = HCL

That is a harmful strong acid that fumes. We used to use it quite a bit at school.

Sorry, I am terrible with names of chemicals, but much better with chemical formula like HCL. I learned most of my chemistry in another language.

Hydrogen peroxide (H2O2), potassium dichromate (K2Cr2O7) and potassium permanganate (KMnO4) are all oxidizers and likely do the same thing for diatom cleaning.

H2O2 is the weakest and safest.

KMnO4 is the strongest oxidizer of the three. When used alone, it is also pretty safe and can be used for food cleaning. But it may explode or produce harmful fume when combined with other strong acids/chemicals.

K2Cr2O7 will hurt human skin and can be combined with sulfuric acid for cleaning glass.

Having no experience with diatom cleaning and going strictly by book knowledge, I would probably start my first trial with (permanganate) KMnO4 alone. Boil if necessary.

If that does not do the job, I would use very diluted (10%) sulfuric acid BEFORE KMnO4 and wash the acid away before adding KMnO4. Though 10% sulfuric acid should not react with KMnO4 to produce harm (but 98% concentrated sulfuric acid will react with KMnO4 to produce explosive chemicals).

Reference:

https://en.m.wikipedia.org/wiki/Chromic_acid

https://en.m.wikipedia.org/wiki/Potassium_dichromate

https://en.m.wikipedia.org/wiki/Potassium_permanganate

Also google search for "MSDS chemical name". MSDS= material safety data sheet. Most are available here: http://www.sciencelab.com › msds

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Re: Doing Diatoms

#15 Post by rnabholz » Sun May 15, 2016 2:26 pm

Thanks for sharing your knowledge zz, much appreciated!

Just wanted to add a note, the Hydrogen Peroxide that I used is 35% "Food Grade". Significantly stronger than the drug store variety. I edited the post to reflect that distinction.

I am not sure what if any impact that may have on your advice, but wanted to be sure it was understood by all.

Thanks again

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Re: Doing Diatoms

#16 Post by zzffnn » Sun May 15, 2016 2:36 pm

Rod,

Your 35% hydrogen peroxide is much stronger than the usual 3% version.

I would guess that is still not as strong as potassium permanganate (KMnO4) solution in slightly acidic PH. But it depends on the final concentration and reactants. To know for sure, you would have to ask a chemist like eiman.

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Re: Doing Diatoms

#17 Post by 75RR » Sun May 15, 2016 3:48 pm

Interesting post - sounds fun. Well done!

If 35% hydrogen peroxide works for you, and by the photos it certainly seems to, I would stick to that.
No sense looking for stronger and potentially dangerous chemicals to substitute it.

P.S. This would make a very good Microbehunter magazine article.
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Re: Doing Diatoms

#18 Post by zzffnn » Sun May 15, 2016 4:28 pm

Low grade potassium permanganate (KMnO4) solids may be much cheaper than 35% hydrogen peroxide solution, per effective unit (or dollar for dollar considering effectiveness). The solids should have longer shelf life too. It is quite safe, when used alone.

But since Rod already has a bottle of 35% peroxide, he may want to finish that first. Its shelf life is not very long, once opened.

And I forgot to mention about Liquid-Plumr. Its active ingredients include base (hydroxide), hypochlorite (for chlorine like effects) and surfactant. It does not work well, if used together with acids.

Oxidizers may work better than Liquid-Plumr for diatom cleaning.

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Re: Doing Diatoms

#19 Post by rnabholz » Sun May 15, 2016 5:45 pm

75RR wrote:Interesting post - sounds fun. Well done!

If 35% hydrogen peroxide works for you, and by the photos it certainly seems to, I would stick to that.
No sense looking for stronger and potentially dangerous chemicals to substitute it.

P.S. This would make a very good Microbehunter magazine article.
Thanks 75, glad you liked it, and it is fun.

Agree about standing pat on my "recipe". I have no training except long atrophied high school chemistry, and so safety is my prime consideration playing around with these chemicals.

As far as an article, it would need av good deal of polishing to meet that standard, but thanks for the thought.

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Re: Doing Diatoms

#20 Post by rnabholz » Sun May 15, 2016 6:02 pm

Regarding the drain cleaner, I had another thought to add.

Because it is formulated to clear clogged drains, in the interest of making it more effective by causing it to adhere to the clog, it is formulated as a gel.

In that form, mixing it with the diatom material was made more difficult requiring a good deal more manipulation of the material than was necessary with the thinner Hydrogen Peroxide.

I believe the extra handling contributed significantly to all of the broken forms seen in the first samples.

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Re: Doing Diatoms

#21 Post by JimT » Sun May 15, 2016 11:02 pm

Rod, good grief! What an amazing process you did and what patience to go through all the steps to see the final results. Way past my "Pay grade" but I appreciate your industry and the images are as good as a person could purchase.

Totally well done.

JmT

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Re: Doing Diatoms

#22 Post by rnabholz » Mon May 16, 2016 12:02 am

Thank you Jim.

The process took a bit longer because of the false start with the first cleaner. Once I had the right stuff, the cleaning and mounting process was just a couple of evenings - half of that was just letting it sit for 24 hours.

The Centrifuge contributes a great deal to the speed. Without spinning, one would have to wait for the samples to settle after each wash, and that can take a couple of hours each time.

Thanks for the kind words and interest. Your timing is perfect, I was coming back on to post the first single form image.

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Fontana #3 Two.jpg
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Re: Doing Diatoms

#23 Post by rnabholz » Mon May 16, 2016 3:44 am

Another from the same site, same set up. While this one may not appear tack sharp, this is a small form, and the detail is pretty hard to make out visually, so I am pretty pleased with this image.
Fontana #4 Three.jpg
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Re: Doing Diatoms

#24 Post by rnabholz » Mon May 16, 2016 1:41 pm

Here is a reference that offers a variety of cleaning protocols, including some using chemicals discussed in the thread.

https://www.google.com/url?sa=t&source= ... UoS6hH_ZSA

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Re: Doing Diatoms

#25 Post by Charles » Mon May 16, 2016 2:34 pm

Hi Rob,

I'm following this as I too am interested in diatom recovery and viewing.
rnabholz wrote: Just wanted to add a note, the Hydrogen Peroxide that I used is 35% "Food Grade". Significantly stronger than the drug store variety. I edited the post to reflect that distinction.
Reading through different offers of 35% food grade H2O2, they indicate it is actually only 17.5% H2O2. I've notice that Reagent grade H2O2 is 32% and only sold to schools and industries but you can get the 17.5% - 18% which for you seems to be working quite well.

There are some drain cleaners with Sulfuric Acid. One is sold by Home Depot called Buster. http://www.homedepot.com/p/Buster-1-qt- ... /205137550
I wonder how that would work. The HCL (Muric Acid) would break down clays/plant material and some of the other impurities as well.

Keep up the good work!

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Re: Doing Diatoms

#26 Post by rnabholz » Mon May 16, 2016 2:50 pm

Thanks Charles.

As mentioned earlier, I am not much of a chemist, and so defer to those with those skills. For reference, here is the source for the Hydrogen Peroxide that I used:

8 Oz Certified 35% H2o2 Hydrogen Peroxide Food Grade & FREE 1 ounce Filled Blue Cobalt Dropper bottle. SHIPPED FAST! https://www.amazon.com/dp/B00PBB268M/re ... oxb4KAXZX0

As you can see, they emphasize the 35% thing pretty strongly, but whatever it is, it works.

Regarding drain cleaners, I would say that there is enough evidence that they work for many that it is certainly worth trying. Inexpensive, readily available everywhere, and formulated to be reasonably safe for consumers, it is a very attractive option. For $3 you can give it a try, and if it doesn't work put the bottle under the sink for that inevitable clog... ; ^)

Thanks for the interest.

Rod

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vasselle
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Re: Doing Diatoms

#27 Post by vasselle » Mon May 16, 2016 5:00 pm

Bonjour
Très bon sujet sur le ramassage des diatomées.
Merci pour le partage cordialement seb
Microscope Leitz Laborlux k
Boitier EOS 1200D + EOS 1100D

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rnabholz
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Re: Doing Diatoms

#28 Post by rnabholz » Mon May 16, 2016 9:33 pm

vasselle wrote:Bonjour
Très bon sujet sur le ramassage des diatomées.
Merci pour le partage cordialement seb
Merci Seb

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KurtM
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Re: Doing Diatoms

#29 Post by KurtM » Tue May 17, 2016 11:58 pm

I love this thread! Now that I'm back home, I'll have to post one similar to it. Or maybe I should wait until all my new stuff is in?

After Rod emailed me about his new electric centrifuge, I said I wanted one too since my "Armstrong centrifuge" gets mighty tiring after a while, and you don't even get ice cream at the end of all the cranking. So Rod alerted me to an eBay ad for one very much like his, from American Science & Surplus, even, an old favorite business of mine from way back. And now that I'm home I had 'em ship it, should be here later this week.

Love the slide templates. I made a similar deal out of posterboard after seeing the idea somewhere on the interwebz, been meaning to pass it along.

I have some real slide ringing cement coming (asphaltum), which I badly need to greatly improve my slides.

In the pile of mail that accumulated while I was on the road, I found the ammo I had ordered for my Brother QL-570 label printer that I snagged on eBay a few months ago, and after playing with it a short while I'm almost drunk imagining how much this baby is gonna improve my lab life. Here's a sample from only a few minutes hacking away before reading the (online) manual:
Attachments
5-17-16 first labels1024px.jpg
5-17-16 first labels1024px.jpg (142.35 KiB) Viewed 10128 times
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)aol(dot)com
https://www.flickr.com/photos/67904872@ ... 912223623/

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rnabholz
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Re: Doing Diatoms

#30 Post by rnabholz » Wed May 18, 2016 2:31 am

I'm such a swell guy that I turned Kurt on to a centrifuge in stylish Avocado Green WITH a timer. The executive model....

Love the label printer. I tried to format a template to print them in a laser printer, but lost patience with it. Plus you have to print a whole sheet at a time, not very handy for this application.

I still need to figure out the slide ringing piece. Too busy looking at diatoms.

Made four new slides tonight from the Wapsi river material. Got a much better (thinner) density with these. Pleased with that.

Glad you're home, now get busy..... ;^)

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