No, inch of fish per gallon is some left over rule from early fresh water days. As long as water quality is managed and you avoid stress from over crowding, there isn't really a rule. If you see fish fighting for space, you have too many or the wrong tank mates. If everyone gets along in their own little area, eat well, and don't hide from bullies, you're ok. Depending on tank style (reef, FO, etc) you want to be able to manage waste. If NO3 keeps climbing, even with water changes/skimming, you've got too much. If it's a fish only, it's easier. Reefs probably require greater control of water quality.

yes thats right apologies for leading you the wrong way

Nono not a problem,
Thank u guys,
I was thinking of having a reef tank and potentially putting 2-3 fuzzies in the tank (30-35g)