# 3-gallon planted snail bowl (no heater, no CO2)



## alphaparrot (Nov 28, 2017)

I had some herbivorous pond snails (Greater Pond Snail, Lymnaea stagnalis) in my 10-gallon that were threatening to eat my oriental sword if I didn't move several thousand dollars to a bank account in Zurich, so I set up a 3-gallon bowl for them to live in with plants they could safely munch on. The bowl is a pretty nice plastic material (found on amazon), which I've filled with a sand/potting soil mix (washed and baked), topped with stones collected from the Lake Ontario shoreline. The light is an IKEA Jansjo LED desk lamp, and I've added a small amount of filtration with a small DIY sponge filter powered by a Tetra Whisper 10. I'm assuming the bioload is small enough that really the plants will do all the filtration, but I mainly wanted to make sure there was water circulation, and I figured I might as well stick a sponge on that. The spherical shape magnifies everything inside, and hides certain parts of the tank as well, so the filter is completely invisible from almost every angle except from behind the bowl or directly above. The bowl is now about 10 days old, and the floating plants are growing quickly (will probably thin soon), the moss is growing, and the snails seem very very happy. And I'm generally very happy with how it looks.

Because of the very low bio-load, I'm not doing any water changes, just topping up every few days. Aside from thinning out the floating plants, this is my lowest-maintenance setup. We'll see how it does!

Plants:
Trident java fern (from Ciddian, thank you very much once again)
Flame moss (also Ciddian)
What may be parrot's feather (again, Ciddian)
Water sprite (floating)

Animals:
2 Lymnaea stagnalis (greater pond snail--grows to 3 inches across, eats plants)
An indeterminate number of Physella acuta that hitchhiked on plants (acute bladder snail, grows to 1 cm across, extremely speedy but does not eat plants)

Initial planting:









10 days:









Snails:


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## alphaparrot (Nov 28, 2017)

I should note that another reason to put a small sponge filter (or air feature of any kind) in a bowl like this is for dissolved gases. You don't technically need a filter of any kind in a planted bowl like this (see e.g. MD Fishtanks on youtube); the plants and substrate will do all the filtration, but the tricky thing about a spherical bowl like this is that the surface area for gas exchange is more like what you'd get for a 0.5-gallon or 1-gallon tank, not a 3-gallon. That means that without doing anything special, dissolved CO2 and dissolved O2 are quite a bit lower than you might expect. Running an air stone or a small sponge filter helps to increase that, both by direct injection of additional gas and by disturbing the surface, which increases gas exchange.


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## Karin (May 21, 2019)

that is lovely. i've been thinking of setting something like this up for shrimp. though i haven't gotten past the planning stage (and the bowl is still in use as a terrarium...).


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