Hi! There is currently a 50% off sale at my lfs and they are getting a shipment in tomorrow. Most of their freshwater fish will be gone by Friday to Saturday. I want to buy some Cory cats and cardinal tetras. I won't be able to go Friday or Saturday because I'm very busy both days. The problem is that I have some cardinal tetras and Cory cats already in my qt and they've only been there since Saturday. It's a 5 gallon qt tank with 9 cardinal tetras, 8 habrosus cory cats, 2 gold rams, 4 otocinclus, and 1 red lizard whiptail pleco. I know this isn't ideal but the fish are not stressed. I change about 2 gallons everyday. Do you think it's safe to move out the rams and pleco (because they produce the most waste) to make room for the new fish? I also have a 10 gallon with 8 serpae tetras but there's more of them going in there so that tank is going to be pretty full. They have also been in since Saturday. My logic is that the least amount of fish I move means the least chance of a disease getting into the main tank. All the fish look healthy so far, nothing to worry about yet. Is it mostly safe to move a few fish into my 75 gallon tank?