QUOTE(ConverseWithMyConverse @ May 13 2008, 05:59 PM)

I don't have enough filtration? I was sure I had more than enough. Both are for tanks up to 100 gallons.
Aquarium suppliers rate their filters according to different standards than goldfish keepers have. Tropical and marine fish typically do not need as much filtration as the fish are usually small and produce less waste. Thus, manufacturers may rate a power filter as "up to 50 gals" and the filter will be quite sufficient for these types of tanks.
However, goldfish keepers ignore such labels and look for its flow rate. This is the water turnover, or how much water the filter processes in 1 hour. For example, the Aquaclear 50 filter says it's for tanks up to 50 gallons, but its flow rate (gallons or liters per hour-- GPH/LPH) is only 200 GPH.
The general rule is 10x the tank volume in filter flow rate (GPH). This is the minimum requirement-- many people prefer to have more filtration, especially with bigger fish. For example, a 10 gallon tank with one goldfish requires a 100+ GPH, a 20 gallon needs 200+ GPH, etc.
So in your case, you have 850 total combined GPH, but your tank is 90 gallons, and it's fully stocked. The bare minimum suggested rule would be 900 GPH or more. An overstocked tank, with 10 fish in a 90 gallon tank would need even more filtration. There's plenty of room for 10, but the extra load means you need more filtration.
I would suggest that you get another tank, and move 2 to 3 fish into it with proper gallonage/filtration. That way, your 90 gallon won't be overstocked and your filtration will be adequate.
I hope this was helpful!
Oh, and Casper is absolutely gorgeous. Any idea who the parents were?