CT has no application fee. But be careful when designing your system because the larger your system is, the more the state requires you to treat your discharge. I got lucky and all im going to need to do is chlorinate. Also A.T.T.R. you beter be careful with setting up before being approved. I know for a fact that I cant set up my system until I get approval form the state. There are several fines imposed, not to mention they can shut you down. There are alot of environmental laws surrounding aquaculture that have recently been established. If your system is a great deal larger than 500 gallons I would think twice about requesting a permit.