MicrobeHunter.com Microscopy Forum

KurtM wrote: ↑

Sun May 31, 2020 12:41 am

Charles, can you add a word on where you obtain your chemicals? Muriatic acid I know to be available in home improvement/hardware stores, but any comment regarding concentration? I seem to remember there being some discussion of having to be careful to buy the 'strong stuff'. And where do you get sulfuric acid? I bought auto battery electrolyte some time back, but it sure didn't seem to do much.

Hi Kurt, I get most of my chemicals, I get off the Internet stores or eBay. Just Google search for the chemical you need. The Muriatic acid I get is about 30% and came from hardware stores (Lowes). You can also get them at swimming pool stores as you use HCl to lower the pH of pools. The 'weak' battery acid containing sulfuric acid can be heated to get a higher concentration. Sometimes shipping prices of certain acids are higher. I've found Nitric acid on eBay and have some coming and may use it more than the Sulfuric acid or in combination.

deBult wrote: ↑

Sun May 31, 2020 5:49 am

The diatoms shop in Holland sells pre-cleaned diatom samples (Website in English) and Mountants and other gear you may need.

So no unknown dangerous acids to mess around with: https://www.diatoms.nl/index.php?seo_path=samples

Happy customer only,
Best, deBult.

I haven't personally had a go with these but a very experienced diatomist once told me the cleaned diatoms from diatoms.nl are second to none.

deBult wrote: ↑

Sun May 31, 2020 5:49 am

The diatoms shop in Holland sells pre-cleaned diatom samples (Website in English) and Mountants and other gear you may need.

So no unknown dangerous acids to mess around with: https://www.diatoms.nl/index.php?seo_path=samples

Happy customer only,

You are right deBult. I have bought stuff from him also (Pleurax) and he has a limited amount of diatom samples, but I also like doing things myself. This allows me to get samples some others don't have and also go through the process myself. Yes, acids can be dangerous and should only be used with caution, proper protective equipment and knowledge of what it's properties are, especially the dangerous ones.

I have completed about five water changes to the sample heated in HCl. I have been only waiting about four hours to let things settle and then siphon off the liquid and putting it in pickle jars. Due to short period of time letting things settle (ideally you would want to let it settle for 24 hrs) I can see fine sediment in the bottom of the jars. Later I will siphon off the liquid in the pickle jars and save the sediment.
Each sample gets it's own flask and waste jar to prevent cross contamination of diatoms from each site.

I started cooking the sample now in Sulfuric acid. The flasks had about 30ml of sample and water and I added about 30ml of acid. I placed the flasks in a metal pot with enough water to keep it from boiling off. You don't want too much water where the flasks float off the bottom and could tip over. I'll cook them for about an hour and then start the dilution with distilled water after cooling.

Disclaimer: I should note that using acids can be very dangerous and I do not imply everyone should be doing this. You need to know the properties and dangers of each acid used and use proper safety precautions. Improper user of acids can cause bodily harm. Perform at your own risk.

I'll add another endorsement for Michel Haak at diatoms.nl. I've been doing business with him for some years now, and he's always been a delight to trade with. His cleaned sample material is indeed wonderful for making your own slides, and his finished slides are likewise first class.

deBult wrote: ↑

Sun May 31, 2020 5:49 am

The diatoms shop in Holland sells pre-cleaned diatom samples (Website in English) and Mountants and other gear you may need.

So no unknown dangerous acids to mess around with: https://www.diatoms.nl/index.php?seo_path=samples

Happy customer only,
Best, deBult.

Hi together,
when you have a marine sample - at which point do you remove salt?

Bob

You would need to remove the salt first through several water changes.

I've washed all the acids out and have pretty much removed most of the fine sediment by timing the settling and water changes.
Since it was the easiest to clean, here is the Nevada diatomite sample, acid washed and cleaned.

I put 10-12 drops onto a slide and gently warm them until the water evaporates. Gentle warming is the key to let the diatoms settle down to the slide, because if you heat too quickly the diatoms migrate to the edges.
Making strew slide: This is the Nevada cleaned strew slide with the glass needle: The start of the Nevada keeper slide:

Hi Charles,
your sorted diatom slides look great! They will make high end photography a lot easier.
It is an advantage of the thoroughly cleaned diatom material that there remain no sticky contaminations and the frustules can be picked out of the strew slide.

Bob

Thank you Bob.

There are 'dirty' diatoms on that keeper slide. I start by picking forms off a strew and will pick off a dirty one or even partial ones until I find some that are clean and perfect. Those will go to the top of the slide and I will remove the damaged ones and dirty ones. The dirty ones, which I want to keep, I can clean in a drop of distilled water on a separate slide and even chase/rub them on the frosted end of the slide.

An update to this project. I have tried to clean the Nevada specimen of the very fine debris and particles by monitoring the settling times after adding distilled water to 10ml test tube and agitating. Used drops of sample onto a slide in five minute intervals and examining under a scope to view the presence or not of diatoms in the drop, and came up with 45 minutes before siphoning off the fine particles. I'm not concerned with the heavy non-diatom particles as I can pick out the clean diatoms from it.

I posted a video on YouTube of moving the selected diatoms from a strew slide to my keeper slide.
https://www.youtube.com/watch?v=UlZhqMU ... e=youtu.be

Hi Charles,
so the water contained diatoms until about the 45th minute?

Bob

Fascinating process. Big thanks for sharing with us!

I think you have demonstrated that this is not an aspect of the hobby I should pursue. I’m far, far too impatient. But, if you have any slides in your “junk” pile that aren’t up to snuff, let me know. I’m sure that even slides you are unhappy with are much nicer than anything I have!

MicroBob wrote: ↑

Thu Jul 02, 2020 4:52 pm

so the water contained diatoms until about the 45th minute?
Bob

Hello Bob,
Yes, about 45 min and most of the diatoms from this sample have settled in a 10 ml tube. It will vary from different samples. Samples I tested in my other post took about 5 minutes.

Thank you Zuul. It really isn't that hard. It just a matter having a proper setup, tools and time doing it. Someone said it takes about 10000 hours to be proficient. I have about 1000 hrs in doing this.

I'm admiring how fine your needle is!

I know you've discussed needle-pulling, but I have been unable to do anything in the lab because I haven't seen my home since February. But when I do get back, that's one thing I want to tackle right off: improving on my needles.

Hello Kurt,

Hope you are able to get home soon. needle pulling is a matter of temperature (low), technique and practice. I've gotten to where I get two needles with one tube and very little waste.

Thank you all for this excellent conversation

Charles, I finally made it home today, and wonder if you can point me to your needle-pulling discussions, and/or anything else on the subject you think worthy of attention?

I intend to revisit the needle-puller apparatus that Keith has been working on, as it especially piques my interest. But I have steady hands, and rather enjoy challenges to just how steady they are...

[EDIT] That sounded a bit tactless. So for a bit of back story, Keith has told me himself, in no uncertain terms, that he turned to investigating needle-pulling mechanisms precisely because he considers his own hands insufficiently steady for freehanding it. And as far as I'm concerned, a pulling "jig" can only mean increased precision and/or predictability, so most definitely worth a look.

Thanks You for Show us this excelent work.

Sabatini wrote: ↑

Wed Jul 08, 2020 8:12 pm

Thanks You for Show us this excelent work.

Thank you Sabatini.

KurtM wrote: ↑

Wed Jul 08, 2020 12:47 am

Charles, I finally made it home today, and wonder if you can point me to your needle-pulling discussions, and/or anything else on the subject you think worthy of attention?

I intend to revisit the needle-puller apparatus that Keith has been working on, as it especially piques my interest. But I have steady hands, and rather enjoy challenges to just how steady they are...

[EDIT] That sounded a bit tactless. So for a bit of back story, Keith has told me himself, in no uncertain terms, that he turned to investigating needle-pulling mechanisms precisely because he considers his own hands insufficiently steady for free handing it. And as far as I'm concerned, a pulling "jig" can only mean increased precision and/or predictability, so most definitely worth a look.

I don't know that we discussed hand needle pulling in detail. I use two pulls. One, to heat it until I can put a couple of twists in, to make it solid, along with a small partial pull to get the diameter tapered down. And then back into the flame briefly for the second pull to separate them. When I'm ready to do the second pull, I will remove it from the flame, when I feel a small give, and simultaneously, give it a good pull. If it is kept in the flame too long during the pull it will be too wispy. If the pull is unsuccessful, I put both ends back into the flame to join/melt together and then twist and pull again.

I am intrigued by Keith's mechanical assisted pulling rig, which would be really nice to get consistent usable needles.

Thanks Charles. And what kind of heat are you using, butane torch or alcohol lamp or what? The micro torch runs awful hot, but that can be mitigated with distance. I have trouble getting consistent flame action with alcohol lamps.

Kurt,
I am using the alcohol lamp. I put the wick as far down as it will go and still maintain a flame. Sometimes the wick needs to be trimmed.

I moved on to the Santa Monica diatomite last weekend...Friday pm to Sunday pm. I cleaned it as well as I could and the strews are still very 'dirty', mostly broken or damaged and very few to pick from, as can be seen in the first photo below. Still there are some very interesting diatom species and at last count there were at least 30+ different...if only I could get clean frustules. The keeper slide represents going through 12 strew slides. Photos were taken through the B&L SZ7 from various magnifications or 22X - 110X (15X eyepiece and 1.5 Barlow lens)

The strew: The Keeper slide left side: Keeper slide right side: Keeper far left magnified: Keeper far right magnified:

Some other views of the keeper slide:

Was hoping to get this update done earlier but had to clean up a lot of down trees and damage when hurricane Isaias came for a visit. And then a couple days later, a lighting strike set my large 16X12 barn shed on fire. A lovely week and month!

I set about getting the Monterey specimen sorted through. The strews were mostly broken diatoms, spicules and debris as the first 'strew' slide shows. All those diatoms were not in that frame, I had to pull from adjacent fields just so you can see the common varieties. This sample had a lot of the same species as the Santa Monica deposit as they are on the same West coastline but there were a few differences. Photos are not sharp as they were taken through the B&L SZ7 and Canon EOS T3i.
What the strews look like: Part of the Keeper Slide: And closer views of the species:

And some more: