Help, please

[Pescador]

Hey
How big is your tank? If you have 1 to 1 1/2 lbs. of live rock per gallon you don't need the biowheel or any other media for biological filtration.
You could probably keep one of the filter trays for mechanical filtration if you change it frequently.
If you can remove the wheel and trays would that would free up some space in the sump? If it does see what the biggest skimmer footprint is that you could fit in there.
For nitrate levels I think most people with corals try to keep the levels under 10 ppm. Fish only tanks can be much higher.
I have no experience with sea horses but I don't think many people keep them in a reef because of the high water flow needed and I don't know about their tolerance for nitrate.

[BlueAbyss]

As was said above, biological filtration (the biowheel and apparently the batting that you use in your filter trays) is not needed in reef tanks, that's what the live rock is for. The reason they told you not to change all the filter material at once is for biological filtration... when you change it, you lose the bacteria that populate it. This works for fish only tanks, or tanks with little live rock... it is not needed (and probably the source of your nitrates) in a tank with lots of live rock.

Skimmer tend to work best when they are run constantly. Something about the interaction of the proteins and the 'skin' that forms on the inside surfaces of the skimmer body makes them more efficient when they've been running for a couple days to a week straight, or so I've been told.

It's obvious that you don't have a lot of flow in the display (you are keeping seahorses after all), have you considered adding some live rock to your sump? Larger chunks will have deeper areas that are anaerobic, which provides a place for the nitrate consuming bacteria to live.... while you're at it, you could run some Chaetomorpha algae in there with light, that will also help with the nitrates. Or grow some other macro on the rock.

Some fish do poorly in nitrate laden water... something to keep in mind if your fishes look a little off.

[whatcaneyedo]

The Basics of Filtration for the Reef Aquarium
http://www.advancedaquarist.com/issu...3/beginner.htm

Skimming Basics 101: Understanding Your Skimmer
http://www.reefkeeping.com/issues/20...ture/index.php

Reef Aquarium Water Parameters
http://www.reefkeeping.com/issues/2004-05/rhf/index.php

The Reef Aquarium Volume 3 by C. Delbeek & J. Sprung
http://www.jlaquatics.com/product/li...ardcover).html