one more question, I bought a 11 liters tank to breed the 100 Ramshorn Snails and 50 shrimps. here is a photo, the pet store guy told me that I do not need a auto thermostat, only a filter is sufficient (he said room temperature is fine for the tank of shrimps and snails). the filter is a bit powerful, I can see it has a strong current in the water.
also i see some snails are floating and do not go down to the bottom, is this normal?
is this tank sufficient without a thermostat even in winter (but the tank will be in the bedroom)?
here is the tank picture.
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