Petsmart sale got the tank, stand,lids, light for $474 brand new.We have the exact same tank and stand.
If I was you I would do three things, add more filtration, like a pair of AC110S. Second lower the stocking of your tank drastically. Third greatly increases the amount and frequency of water changes.
It may not seem bad now. Put will only get worse from here on out as all them fish gain size and start to mature.