LOL, I have to agree! I got told about having a Kole tang in my 30 long tank! Those are some big fish - way too small of a tank. If you are really set on having those fish, you need to get a bigger tank. If you just want to keep the 20, then do some research and consider some smaller species of fish. It all depends on whether you want a FO, or reef tank, or anything else. Do your homework before you buy, and it will save you $ in the long run. Believe me, I've made the mistake of impulse buying and not research what I got, and I paid the price. Just trying to help - you need to get those fish out of such a small tank. Good luck!