how much filter media?

[john]

is 2 cubic feet of filter media/bio balls enough for a 200 g f/o aquarium? what is the formula?

[FMarini]

Hi:
hummmm...i seem to recall something about this years ago. I believe it was measured in gallons of biomedia. I can tell you when i started my 180gal FO I used 8 gal of bioballs, it worked well.
Check w/ coralife they have biomedia in 25gal containers and it has all the approximations on the side. Also be aware that these are approximations, and if you load up the tank w/ heavy polluters it might not be enuf biomedia. Second, I recall the filter media was common in the mid 80's. It much less common now as it clogs readily, and worse become a nutient sink in a few weeks. The nice thing w/ bioballs is that they don't get clogged up. So if you want the best of two evils go w/ bioballs or one of these non clogging plastic biomedia. Last point, you should read up on, and learn about using a deep sand bed (DSB) or DSB w/ live rock. These DSb has far more surface area than a bucket of bioballs ever will, and better they also allow endstage N2 production. As you know wet/dry, or fluidized bed filters are notoritus producers of nitrates. Just a point to consider
good luck
frank

[Fishywannabe]

Fmarini

Your reply got me thinking... (scary isin't it)

My setup in my 110 is a 3-4 inch sandbed. I have approx 100 pounds of 'dead' rock with maybe 10 pounds of live. Its been running with a wet dry for about 10 years like this. As to be expected, this tank has for years had high nitrates. My sandbed has seeded from the limited live rock in this tank, as I have all sorts of worm trails in the sand. I can even count a dozen bristle worms next to the glass as I type this. I have just lately, 3 or so months ago, added another inch of sand, and will probably add another inch on top of this over time.

My question...do you think it possible to begin removing the bio-balls to see if the sand and limited rock can support the tank biologically and help control nitrates at the same time?

I haven't really been bothered by the nitrates until I began reading this board some 6 months ago. I'm guessing my fish are glad I started :)

Thanks

[FMarini]

Hi:
Wow first time for my posts to be thought provoking =^>
Sure i would slowly remove handfuls of bioballs every third week. i suspect you have an established sandbed by now, and a fair amount of live rock (althou if you read any of Dr Rons posts (in his dr ron section) you'll see he believes that when you have a established DSB, it has far more filter capacity than live rock ever would, an therefore he believe that LR is nothing more than decoration. Right now your setup has reduncdancy, w/ the possibility of the wet/dry contributing to some nitrates, my opinion is to remove it.
let us know what you decide
frank

[Fishywannabe]

Thanks very much for the vote of confidence. I have been leary of removing the bio-media. Think I'll give it a shot though.

The bio balls that I have are about the size of a golf ball and would probably fill about two-thirds of a standard five gallon bucket. In your opinion, how much of the balls would you remove at one time? I was thinking maybe about 25 percent or so every other week and just monitor ammonia and nitrite levels. Again, I'm leary about the whole thing.

Thanks for the info.

[FMarini]

Hi:
20-25% sounds like a fair assessment. Especially if you give it time in between removals for the DSB and LR to play catchup ball and build up the biofilter.
Just monitor for any possible problems(ammonia and nitratie for sure). Otherwise it reads like you on your way
frank