If we know after a few hands with someone, that they are fish, then what type of fish should we assume that they are? In Grinder's manual by Peter Clarke, he says that there are 4 types of fish: Fit and fold fish, Station fish, aggro fish and whale. Now in my own example, we just saw our opponent give some signs that he's a fish, but we don't have any enough HUD stats in order to tell if they are folding a lot when they limp vs an iso, or if they are folding a lot on the flop(also not enough stats for if they are an aggro fish). So clearly here, we can't know if we have fold equity against them so we can iso them with a wide range. So how should we proceed here? I am asking this question for NL2 since that's where I am playing.

I think that in a situation where we see someone is a fish but don't know what type of fish, we should take a strategy which is going to be between one we would use vs a station fish and one vs a fit and fold fish, meaning that our iso range will be tighter than the one we would use if we were sure that villain was a fit and fold fish and also our range will be looser than the one we would use if we were sure that villain was a station fish. What are your thoughts? I don't think that whales or aggro fish are common. However, if our opponent happens to be a whale then that's good. We can still iso with a wide range. That's what the book says.