from bio balls to fuge.

[saabtech]

i currently have a large sump area that is about 30-40 gallons about 15 gallons of it is filled with bio-balls and i would like to convert it to a fuge.
i would just like to know what process would you take if you were me.
i dont think it would be ideal to just remove all the bio-balls and install a fuge all at one time. should i remove a little at a time from area one and replace it with live rock that when completely exchanged can be transferd to area two of the sump and then convert area one into a fuge?
hope you fallow?!!

[Gseclipse02]

if it was me ( i dont know if im right tho) i would turn off my return pump take out all the bio balls along with all of that water ...

[alton]

Why not setup a seperate fuge and tie into your system? I like to run low flow through my fuge. My current system has been setup since 2001 with a wet dry, bio balls, and a seperate fuge with Nitrates below 5.

[corruption]

Its typically not advisable to remove all of the bio-balls from an established tank at once -- since this is where your anaerobic bacteria are mostly living, removing the bio-balls at once will typically reduce your nitrogen-reducing abilities greatly, potentially causing problems. The recommendation I typically see is remove 1/4-1/5 of the bio-balls at a time, while replacing with live rock if this is your ultimate goal. Alton's suggestion would work very well -- a 'fuge works best when the water is slowly 'dredged' through it -- more contact time for all the bacterium/microfauna involved.

-Corruption

[Europhyllia]

I did it the 'wrong way' with no apparent ill effects.
I already had a hang on fuge, DSB, and tons of rock. After running the system with bioballs for 6 months I just took half of them out. Then a couple of weeks later took the other half of them out, added a filter sock assembly (instead of the wet/dry floss plate)
I already had some rubble under the bioballs anyway. added soem chaeto from my HOB fuge and a clamp on light from Lowes. That's all.
Didn't see any spikes of anything (I test a lot)
So now I have two refugiums - the one in the sump (mostly for nutrient export - I don't know if pods would actually survive a travel through the return pump, etc.) and the HOB that gently flows into the tank giving pods a better survival chance.

[corruption]

The biggest difference there, is you had your nitrogen export already established in other places. If you've not got another filtration method (be it biological, chemical, or mechanical), thats where the potentials for problems arise. Going from bioballs in an area, to an all-out fuge in an area, may be enough to cause that swing.

Don't take that wrong, theres always people that have done things the non-recommended way and come out ok on the other end... me, personally, I would make sure I had another form of filtration available before going that route.

-Corruption

[Europhyllia]

... me, personally, I would make sure I had another form of filtration available before going that route.

I agree but I think for most of us that other form of filtration is in large part the live rock and sand in the display tank. He's not trying to convert a Fish Only system, right?

[corruption]

Yes, but the question is, once the bioload is balanced across all of the filtration methods, when you remove one of those methods if its still sufficient. Thats the main reason for doing a staged approach, because this allows any bioload to transfer to the new 'location', before removing the old 'location'. In most reef tanks, it would likely be able to weather it without a problem, just due to the amount of rock we typically pile in, but if the bioload is high enough that the extra filtration is truly necessary to maintain it, there can be problems.

-Corruption

[allan]

Mom, I think you probably negated a significant swing also by doing half, waiting a few weeks for the bacteria to get where it needed to be before doing the other half. By then the rest of your system had already compensated. Besides, with the sand, rock and HOB your bioballs probably only took care of what 20% to 30% filtration for your system? If those numbers are right, using your method you only reduced capability by 10-15%.

Just thinking out loud of course.

[ErikH]

I would completely remove the bioball setup and just put in a tank with no baffles. Load it with brand spanking new dry sand, and fill it with ESTABLISHED LR. Have your input on one end, and put a return on some rock on the other side. Very simple. Then you can add a clamp on light and some macro and that's all you need!

If you want to come by and see my setup just call me. 209-1233
Erik