How much is too much?

I get what yorue saying Mr Bill but you are only accounting for one variable. With there being a limit on the amount of O2 a gallon of SW can hold and what that means to a fish is whats important obviously, what he was stating is that there is no limit not on what it can hold but how fast it can be replinished. You have two variable there, surface area of gas exchange, and gph of water moving and surface agitation to promote gas exchange. If your surface area is limited you can always increase the other variable ( surface agitation and gph of flow)to compensate. Now I am sure there will eventually be a max is for nothing else a 10,000gph would make the tank a toilet bowl for the fish to live in an smash themn agaisnt rocks, btu theoretically it can be done and therefore you can have an unlimited amount of fish due to an unlimited capability of dissolving O2 into the SW.

This however SHOULD NOT be done for many many many other reasons

 

Seems the OP Is leaving out the most important aspect here and that is what's best for the fish!!! As a FW keeper for more then 35yrs it actually made my stomach sick to read how many and the type of fish are being kept in that tank I cannot see how anyone of sound mind with any morals could cram so much into such a small place and think them happy, just because they're not fighting! UGH!!

 

I went ahead and tested all levels and all checked out good. The fish don't exhibit any signs of stress.

 

I feel like one of the biggest issues with a lot of aquarists is the fact that they seem to think they know how to tell if a fish is "happy". Besides surviving, which is very different than thriving" we have no way to measure how happy a fish is. You can argue a fish will always be happier in their natural environment then in a tank because of the space and room to swim, or you can argue that any fish would be happier in a tank because food is plentiful and it doesnt have to worry about predators.
Point is you do not know if a fish is "happy". If the water parameters test ok and you are providing good water quality for your fish, feed them right, and they dont show any signs of disease or aggression issues than who are we to try and tell others that what they are doing is inappropriate because the fish is unhappy??