by Rockfish » Thu Dec 18, 2014 10:19 pm
Hi,
I'm guessing they might be US gallon sizes?
As Caryl said, the fish you have are too large for a 10 gallon tank, so it's good that you are getting a larger tank. To help the fish to survive until then you need to minimise wastes in the tank.
You can do this firstly by minimising the waste produced, which means cutting down on the food - maybe feed only every other day, or at least cut the portion size down. I would also try to introduce a dry (flake/granular) food for the angel and shark to vary the diet (the eel might even learn to eat the dry food). The red-tailed shark is more of an omnivore that needs some veggie food in the diet and using only bloodworm and brine shrimp won't be ideal in the longer term.
Secondly I would do regular water changes (say 25% twice per week) to dilute out the wastes, and the minerals from the fresh water should also help to stabilise your pH and stop it sinking (pH going acidic is a classic symptom of rising waste levels and declining buffer salts - so water changes help combat both of these).