I recently purchased a 29 gallon tank. I purchased two blue neon gouramis a week after I set up my tank. They were fine and then I introduced 7 tetras and two bala sharks a week later. One of the sharks died immediatley. The rest of the fish were fine so I replaced the dead shark with a new one. Then I noticed the first signs of ICH. That same day another bala shark died. I went to the pet shop and they gave me NOX-ICH. I followed the directions on the bottle and they told me to discontinue my carbon filters on my undergravel filter until I finished treatment. Now I have lost all my bala sharks, one tetra , and it looks like my favorite gourami is about to die. He has turned bright purple??? HELPME!!!! QUICK!!!