On my regular tanks I will do a water change and vacuum monthly. I have read that with Oscars you should do water changes weekly. My question is should you vacuum weekly also? I know his amount of waste is about equal to that of my toy fox terrier , but I don't want to take all the bacteria out either . Thank you in advance!!!!

if it is uneaten food waste i tend to remove it constantly if you dont your amonia levels shoot up espesialy if your using feeders shrimp etc

LOL No uneaten food, that I can garauntee. He eats anything and everything before it can even go near the bottom. As soon as he sees me with any food he is at the top of the tank just patiently waiting. Most of his food he will take right from my fingers.

Most of your bio is in the filter or filters. I do 30% water changes and vacuum twice a week. With big Oscars, they produce a lot of waste. I relate it to myself. Can I survive with a little food and marginal liquids or should I get good food and better liquids on a daily basis. In other words, If I'm going to have them, I'm going to take care of them the way it should be done.

cleaning your tank wont affect your bb at all. in my set up i vacuum and do a 50% water change weekly and have never had any spikes because of it.

Thank you very much! I am learning as I go with him. I have always dealt with small community fish mollies, tetras, etc etc. He is pretty big, about 10 long right now so he has more to go, but I am hoping to keep him healthy and happy. I give him alot more food than what he got at his last home and his color has gotten alot brighter than it was a couple of weeks ago. Overall I think he is happy with his new home.

oscars are fairly easy fish to keep. all you really need to do is give them lots of room to grow(big tank) feed them a varied and healthy diet with a quality pellet as a staple and keep their water in good condition. if you do that your o's will grow to be big and healthy specimens.