Some of my current micro habitats

[Crater Eddie]

This 10 gallon tank was started this past fall using aged tap water and gravel, and seeded with water from a pond in town that I often use for cultures. Not evident in this photo is a buried airstone set to release a small stream of bubbles. Only this odd algea that produces lots of bubbles of it's own will grow here, although the tank is jam packed with daphnia, copepods, ostracods, and snails. A couple of drops of 7-7-7 fertilizer added late winter didn't seem to help the algae. You would think there would be hydra in here, as the plant you see floating on the surface usually is a good source, but no dice. All spirogyra added to this tank dies withing a few weeks.



This 2 gallon tank was started about the same time as the above with water from the same pond (no tap water) plus a good helping of mud and leaf litter. It started out with a soft sort of algae which you can see is mostly dying out. A small patch of spirogyra added about mid winter has finally taken hold and is making a good showing. This tank has a very good and varied protist population.



This plastic pretzel jar was started last summer from a different pond, including mud and leaf litter. This was the source of the dragonfly that I showed you this winter. After the dragonfly emerged this jar had an amphipod population explosion, and is now packed with the critters. The once clear water has recently turned murky brown and most algae have disappeared. This was the source of the spirogyra seen in the 2 gallon tank.
I have tried transplanting amphipods from this jar to both tanks with zero success. They swim around for a few hours then vanish.

All three tanks sit in the same north facing window, with lights running on the same timer set to about 15 hours on cycle.
Water lost through evaporation is replaced with collected rainwater.

CE

[75RR]

Love the second one, gives a very real sense of an alien world. Wish I had somewhere to put one.

[Hobbyst46]

Thanks for the informative post!
In my previous fish tank, green algae arrived as an unwanted guest, together with Elodeas and similar aquarium plants, and thrived under direct sunlight - even the weak afternoon light - as well as the violet-bluish fluorescent light that is commonly fitted on fish tanks in order to promote the growth of the "legal" water plants.
IMO, the fine silt in mud, when dispersed in water (in contrast to gross sand) blocks light from reaching the algae in the tank, and thus, inhibits their growth.
I would add only tiny quantities of fertilizers - on the ppm level (mg of solid fertilizer per liter of tank water). In a fish tank, fish supply all the essential minerals for algae.
I hope to be able to start a fresh water algae/plankton tank one day...

[Crater Eddie]

These micro environments are a lot of fun to tinker with over the colder months. When it warms up a bit I might try setting up an outdoor ecology similar to what Charlie G described some time ago. I think if I pitch it to the wife as a "water feature" for the front yard butterfly garden I might have a chance.
CE

[coominya]

I think if I pitch it to the wife as a "water feature" for the front yard butterfly garden I might have a chance.
CE

She'll see straight through that. Say your going to breed gold fish as a passive income stream

You have motivated me to go out and search for some more weed for my little tank. It looks relatively barren compared to yours.

[MicroBob]

I think if I pitch it to the wife as a "water feature" for the front yard butterfly garden I might have a chance. ;)CE

Say your going to breed gold fish as a passive income stream

There really is a lot of practical microscopy experience collected in this forum!

[Crater Eddie]

Well, with the crazy spring weather we are having so far, I'll have a while to think about that.
But getting back to the algae, what would be a reasonable solution to "feeding" an indoor algae culture? I know that the nice layer of mud on the bottom of the tank or jar will go a long way, but in a case where that isn't practical, what might be used? I don't want to add fish to the equatiion.
CE

[zzffnn]

Nice habitats, CE!

Maybe ask for some water from a fish store (pet store or market that sells live fish)?

Or try:
https://www.jstor.org/stable/2993226?se ... b_contents
and
https://www.google.com/amp/s/www.resear ... rogyra/amp

Aged tab water may still contain toxins though. Think about Flint, MI. If there is not enough water from original habitat, you may use reverse osmosis water or distilled water. They won't be as good as original water, but should be much better than aged tab water.

[Crater Eddie]

Both useful links, thanks. I have read the "Hints on Collecting and Growing Algae for Class Work" before, but it had been a while. The other link discusses the algae nutrient medium BG-11, this looks interesting, I'll have to look into that.
I am beginning to suspect that the silicone used to seal the corners of the 10 gallon aquarium might be the culprit. This is the tank I found at the dump a couple of years ago and had to re-seal. The general purpose silicone sealer found at the hardware store is reportedly loaded with anti-fungal agents and who knows what else. I was careful to choose a tube that did not advertise it's content of fungal suppressing agents, but it could well have contained them anyway. Whatever it is, it isn't affecting the snails or daphnia or other similar critters, but perhaps it is inhibiting the algae. I am temped to take this tank down, strip it, reseal it with known aquarium grade sealer, and start again. If I do that I'll use pond water to fill it instead of aged tap water, and a generous layer of pond mud in the bottom instead of gravel. Who knows, I might end up with another dragonfly nymph or two.
CE

[billbillt]

Hi CE,

Thanks for sharing this with the forum... These microhabitats are a great source of wonder and interest to more people.. I love to read your updates to this project.. Please keep it coming!.....

Regards,
BillT

[Crater Eddie]

Thanks Bill, it is a lot of fun, I'm glad other folks are interested.
Regarding #3, the pretzel jar, I believe I can blame it's altered state on the amphipod explosion. I was puzzled as I thought they ate leaf litter and such things, but a little reading reveals:

"...feeds on detritus and sediments, coarse and fine particulate organic matter, filamentous algae, diatoms, animal matter, its own species, and zooplankton such as Daphnia spp..."

Bingo! As the population increased they ate all the algae and turned the jar into a murky wasteland. So it seems that one needs to keep the amphipod population in check if one wishes to maintain an algae culture in the same jar with them. I guess I should be glad that my attempt to transplant some into the 2 gallon tank failed. Still, they are pretty interesting little creatures, I will try to maintain a population of them if I can, perhaps with a predator added for population control. I'll try to save this jar with a partial water change, thin out the amphipods, then try adding some spirogyra from the 2 gallon tank.
CE

[Crater Eddie]

Here is the pickle jar after two partial water changes a couple of weeks apart. Things are greening up nicely again. Still plenty of amphipods here, I drop in a few fish food pellets every week or so for them.
CE

[75RR]

As you say, greening nicely!

Here is an interesting post on light spectrum for plants: http://www.aquaticplantcentral.com/foru ... hesis.html