Your babies should have 20 gal
for the 1st one and 10 gal
for each additional fish. Preferably a long tank. They get huge and pollute the water something fierce.
I just had a water problem in my Goldfish tank due to a big dying Rotala plant (I didn't know it was basically dead, just thought it needed more light
You should have an ammonia test kit, and do lots of partial water changes to keep ammonia in check. Filter system many times what the gallon rating is for the tank. I couldn't believe it myself but after doing more research I was surprised and concerned so I got a bigger tank. Now 32 gal
for my BIG Oranda and Fantail.