I'm just new to this hobby I just had my 36 gallon tank cycled and running about 1 month and 2 weeks. At first I put in 6 danios while cycling and afterwards when everything looks good with the water parameter I added 3 mollies and 2 pot bellied, and 1 albino sucker fish and a big one can't remember the name. Now after a while I have added another 3 silver dollar, 1 gold gourami, 2 African dwarf frog and 1 parrot fish. Unfortunately My friend who's tank was having problem gave me her 2 black moor and I can't say no . Am I over stocked? I'm doing 25% water change every other day coz my amonia is always on the stress side so is the nitrites. I'm looking at getting a 50 gallon tank if over stocked is my problem or maybe just upgrade to a bigger filter? Pease advise. Thank you.