When to eliminate HOB/Biowheel filter?

[Scoot]

I want to remove my HOB power filter. Now that I've got a small sump going, I want to move everything I can off the tank, and just have a return line, overflow box, and a powerhead.

I'm up to 50 pounds of LR in my 75g tank, 2-3" of LS, and params have been perfectly stable for about 3 months, except nitrate, which of course, climbs each week towards 20 before I do a PWC.

I'm running a 10g DIY sump/fuge with about 10 pounds of LR rubble and chaeto. I'm thinking about adding another 10g tank for the fuge, and plumbing it off the sump return line, overflowing (drilled) back to the sump. I can't fit anything bigger than a 10g inside the cabinet because of center support braces (and I'm not brave enough to remove them).

Coralife 125 super skimmer.

Currently 64 watts of stock flourescent lighting, but Monday I'll have 4x65 PC lighting.

24 watt UV (too embarrassed to name the brand, so you can probably guess it).

The only thing I think I'm missing is the mechanical filtering - I'm working on a filter box that will take the overflow flow, and fit over the sump/fuge, which will contain filter floss, filter pads, sponges, whatever, draining into the sump.

Am I safe to remove the Emperer 400 dual biowheel filter? My biggest concern isn't mechanical filtering, but biological filtering.

I'm going to guess my best bet is to remove one of the bio-wheels, wait a week and see if I get any spikes in param's, then remove the 2nd.

Sound like a plan?

PS - the chaeto is relatively new, as is the lighting over the sump, so I'm hoping that will help or eliminate the accumulation of nitrate.

 

[melosu58]

You probably could but you need more live rock in your tank. I always say about 1.5 lbs per gallon. If you could at least get it up to 1 lbs per gallon with the fuge, I would go with your plan of one at a time. Good Luck

 

[Scoot]

Is the concern about more LR because the biowheel provides that much biological filtration, as opposed to the 50 pounds of LR and LS, or is overall filtration the concern? I assumed even with just 50 pounds of LR that there was enough other things in the tank to support biological filtration...

 

[melosu58]

No the bio wheel does not provide that much as compared to the LR. Most accounts I have read say about 1.5 for proper filtration. I have 200 lbs in my 125

 

[MT79]

I assumed even with just 50 pounds of LR that there was enough other things in the tank to support biological filtration...

That depends on how heavily stocked the tank is. If you have a light bio-load then it would probably be fine. However as melosu58 said, 1.5-2 lbs LR per gallon is best.

I'm going to guess my best bet is to remove one of the bio-wheels, wait a week and see if I get any spikes in param's, then remove the 2nd

Sounds like a pretty solid plan. Although I would test a couple times in the first week. I would think it's possible to see a little spike or mini-cylce while the nitrifying bacteria in the tank/LR "catch up". Best of luck and let us know how it goes.

 

[Scoot]

melosu58 - I thought the 1.5 to 2.0 pound per gallon guideline was for full bio filtration, including nitrates. Long term that's a goal anyway.

In the meantime, I'm wondering if the bio-wheels are actually making my constant nitrate climb worse - I'm doing pretty big PWC each week to keep it down to 10.

Of course, something has to eliminate ammonia and nitrite. I'm just wondering if the 45 to 50 pounds of LR I have now are enough to handle THAT part of the process.