Is fluval fx5 enough for 150gallon oscar tank

[coolitz]

this is my 150 gallon freshwater tank

 

[coolitz]

heres another picture of my tank!!

 

[Jmunroe]

Just the 3 fish? FX5/6 will do but I use an aquaclear 110 as well on my 125 oscar tank with one oscar and 10 silver dollars. In the FX5/6 use the sponges and fill the 3 middle trays with as much biomax as you can. I open mine 2-3 times a year for cleaning. I use the AC 110 for mechanical and use just 2 sponges in it. I had to cut one sponges to fit it in as well. I also have house plants in the 110 with the roots stuck in behind the sponges. Nice tank by the way.

 

[coolitz]

I also have 3 parrot fish and 1 upside down catfish with them and hooked up a aqueon 90gallon power filter as backup

 

[Jmunroe]

Ok I'll give it to you straight.... The 3 parrots are overstocking your tank. The 2 oscars and the cat are going to max out your tank. Your going to be constantly battling water quality issues, mainly high nitrates all the time and territorial issues. You'll end up doing 50% or more water changes a day to keep nitrates below 20ppm so your fish don't suffer. Oscars are tough but they like and need pristine water and good diet. If not they will get HITH/HLLE. You can never change enough water on large cichlid tanks.