messy tank

Question
hi, i have 2 Oscars and 1 catfish in a 55gal tank,i don't think i over feed they eat everything i put in ,and what they don,t i screen out,but they are very messy eaters . the cat can't keep up  or won't can you recomend a bottom feeder that would survive and do a better job  

Answer
Unfortunately, you are already overstocked.  I don't know what kind of catfish you have, but most grow fairly large.  The minimum for 2 Oscars is about 120g.  It is recommend that a single Oscar with no other fish needs 75g.  This is also speaking from experience.  I had 1 Oscar in a 55g and I had nothing but problems due to the small size of the tank. They are messy eaters and because they eat food with lots of protein it's harder for the bacteria in your tank to keep up.  Even if you over filter and change the water frequently, you will have problems with ammonia and probably HITH disease.  To solve your problem, you will have to buy a larger tank or find a new home for your Oscars.  Sorry, but I am just being honest.