psi the guy from the fish store says that I should take a ear bud, take the flowerhorn out of the water and apply some methliyne blue on the ear bud and then put on t he areas where the flowerhorn is having these pimplesDear 1 table spoon/5 gallon ........so if you have 180 gallon US/150 gallon Uk (I think that MFK calculator is in US gallon??? ) then add 36 table spoon ...simple is that.....and you should better get an extra medication tank.....and it is better that you should change the water first........
Note: changing water 100% regularly or often removes beneficial bacteria from tank!!!