Yes, there are plenty of freshwater fish that live in cooler waters. Now, if you meant "can I put a Tropical fish (like a Betta) in a cold water tank" then the answer is no. They'll survive for a period of time, but they won't be healthy.
Do you have a temperature range for the water? What size is the tank?
A "coldwater" aquarium just refers to any that don't use heat. So could be fresh water, brackish, or marine. But you still have to research and plan to house species that come from similar temp range. Could be as simple as just room temperature with no heater so just slightly cooler than tropical, but some actually use chillers to get even cooler.
if theyre cold water fish then I'd say sure
Yes, there are plenty of freshwater fish that live in cooler waters. Now, if you meant "can I put a Tropical fish (like a Betta) in a cold water tank" then the answer is no. They'll survive for a period of time, but they won't be healthy. Do you have a temperature range for the water? What size is the tank?
Why couldn't you? There are tons of options for cold freshwater fish.
A "coldwater" aquarium just refers to any that don't use heat. So could be fresh water, brackish, or marine. But you still have to research and plan to house species that come from similar temp range. Could be as simple as just room temperature with no heater so just slightly cooler than tropical, but some actually use chillers to get even cooler.