I've had fully cured rock transfered from one tank to another and had fish in it the same day without problems. The trick is to keep the fully cured rock submerged so there is no die off. You may want to treat the tang for ich in the 12 gallon and do daily small water changes to keep up with pollutants for a few days. Of course none of these situations is ideal and you could always give this fish away on Canreef or a LFS who is set up to take a tang, I'm sure someone would take it very quickly. As you correctly pointed out a 30g is too small for a tang and you would soon require at least a 75g tank to house the fish so it's up to you how far you want to take this fish.
|