Wow, I see this time after time after time. I own a small pet store in southern Illinois. It seems one of my hardest jobs is trying to convince people they already have too many fish in their tank. After stating such they still buy another. The tank tends to fine for a while then BOOM! water chemistry gets a little off oxygen level are low and next disaster strikes. THEN, they come to the store saying all my fish are dying!!! Yes
I tell them you had the tank over stocked
Then I seem to get that deer in the head light look from the customer. Under stocking a saltwater tank simply can not be over emphasized.