Hi guys, I think my black moor may have swimbladder he has been floating at the top of the tank on his side and just floots around in the filter current. He is still moving a little. So I went to the pet shop and they gave me some swimbladder treatment No 13, got home and it said works best with salt, called the shop they said use the treament without the salt first to save some money - problem is its says on the side to remove the carbon from my filter for a week or so... is ths still needed as I am not using the salt. tested the water and all PH etc are normal. Help!!