What temp are you keeping it at? You shouldn't need or be using a heater.
Throw out any inch/gallon rule or whatever you are going by. Those guides are garbage. Water changes have much more of an effect on stocking than tank volume.
What? You need to proofread before you post. Please use complete sentences.
What size water changes?
What is the nitrate concentration in the tank? Tap water?
72F is not tropical, keep it that way. You can do platies, zebra danios and their morphs (long finned, gold, blue, leopard, glofish, etc.), bristlenose pleco, white cloud mountain minnows, and select others.
15% twice a week water changes .
i do not know the nitrate concentration in tap.
a guest earlier was on this topic
so can i have 9 long finned gold zebra danios and 6 rosy red minnows with the goldies
You need to buy a liquid nitrate test kit. I would do larger water changes, at least 25%, but as they grow and you keep stocking that will have to increase as well. It should be enough to keep the nitrate under 20ppm BEFORE a water change.
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