your tank is way overstocked. 1 Oscar will take up the whole tank. this could be the problem. I bet that the water is very cloudy. do not take this as an offense. i have no intention to flame people or make them sad and or mad.
He's not overstocked...he knows everything there is to know about fishkeeping because he gets to be bossed around by experienced people so everyone should stop being mean and honest and just tell him what he wants to hear.
How do I put this. Your fish will die if you do not do anything. From aggression or having a dirty tank. Trust me my 75 gallon 4ft looks small with 1, 14 inch Oscar! Listen to us please.
