pump and filter capacity question -- please help

[gil]

i have a 150g that is heavily stocked with (small) south and central americans. as i grow them out, i will thin the population -- but regardless, the tank will most likely retain a heavy bio-load of messy fish.

here is my current pump/filter setup, which i suspect might be inadequate. suggestions for improvement much appreciated:

overflow box inside tank drops water through two large plastic containers filled with bio-balls and then into a 50g sump.

the sump has a fluval 400 canister filter that pulls water out and then puts it back in. the fluval is loaded with foam pads and ceramic rings (and occasionally carbon if i am filtering out meds). on the return to the sump, the water passes through a UV sterilizer.

the return to the tank is handled by a 700gph pump that is located approximately 10ft below the return. the tank also has a powerhead to generate current, but it not attached to anything.

questions:
should i put more mechanical filtration on the sump? when the tank gets messy (ie with cleanings), it takes a long time to clear up. also, my water is clean, but not CRYYSTAL clear.

is my return hefty enough? 700gph would seem to be ok, but i don't know how to account for the amount of lift it is doing ...

 

[---XR---]

i have a 150g that is heavily stocked with (small) south and central americans. as i grow them out, i will thin the population -- but regardless, the tank will most likely retain a heavy bio-load of messy fish.

here is my current pump/filter setup, which i suspect might be inadequate. suggestions for improvement much appreciated:

overflow box inside tank drops water through two large plastic containers filled with bio-balls and then into a 50g sump.

the sump has a fluval 400 canister filter that pulls water out and then puts it back in. the fluval is loaded with foam pads and ceramic rings (and occasionally carbon if i am filtering out meds). on the return to the sump, the water passes through a UV sterilizer.

the return to the tank is handled by a 700gph pump that is located approximately 10ft below the return. the tank also has a powerhead to generate current, but it not attached to anything.

questions:
should i put more mechanical filtration on the sump? when the tank gets messy (ie with cleanings), it takes a long time to clear up. also, my water is clean, but not CRYYSTAL clear.

is my return hefty enough? 700gph would seem to be ok, but i don't know how to account for the amount of lift it is doing ...

i personally would go with something heftier for a pump on a return tank, over 1000gph imo, but i reallly wouldn't spend the money on that if the water quality is alright, i.e. as long as you parameters, for ammonia, and nitrates, etc are down to a minimum, from the sound of what you have other than that on the tank it sounds like it should be fine.

 

[gil]

thanks for the reply. do you know of anyplace where i can get reliable info on GPH as it might be affected by height of the return? for instance -- what IS my 700gph actually producing? (it came with a bar chart that attempts to explain this dynamic -- but it's not very helpful).