i dont think theres such thing and under stocked theires stocked over stocked and no stock inho because theres no set number of fish to put in its all a round-a-bout system.
When my parents were getting tired of having a fish tank, they basically stopped cleaning it and let the fish die off one by one. At the end they has a 2" Upside down catfish in a 50g breeder all by itself. Because it was a pain to keep up, there were no decor just gravel. The poor guy live for quite a while in there by himself before he passed.
I guess that's why I am such a fanatic now about keeping my tank clean!
no understocked tanks. Although I love the simplicity of a tank with 1 really nice fish. If I ever get rich I'm gonna have like a 3000g tank with one 'pima.
Having room in my tank for more fish is like having $50 burning a hole in my pocket. i wish i could contribute to this thread but I'm overstocked as it is...
well, due to a tank restocking and the lack of nice fish currently at my area LFS's, I have a 150g tank with three redhooks (the only nice thing my LFS's had) and some bushynose pleco's: LOL