Of course I ask because I have a 41 gallon tank with a 10 gallon sump. And I wonder when I add something like a Gobi or a firefish, what are these guys like 5g 10 grams with a 41 gallon tank does a fish so small in size have much impact on the ideal chemistry of medium size reef tank? I mean, I understand the rules we are supposed to go by to maintain good reef chemistry, they say half an inch or inch of fish per gal and I don't know how they came up with these rules since they're not hard and fast, but, definitely ominously limiting. Would a 40 gallon tank hold a school Gobi fish though since these species are so, how do the Irish say, wee? interesting how people can cultivate corals until they are literally growing and spilling out of reef tanks, but people with medium sized tanks are admonished to keep the live fish stock to a bare minimum. Well of course corals dont have digestive tracts like members of the animal kingdom