Wet/Dry question

[bluedempsey]

You all know how a wet/dry works right?
well anyway, my question is: what if you had porous rock * totally under water*
and an extreme amount of air going through it would it work as a bio filter?
like a wet/dry?

 

[rayman45]

im going to use about 10-15 pounds of lava rock in my filter

 

[bluedempsey]

im going to use about 10-15 pounds of lava rock in my filter

what i'm asking is: if the rock was totally under water?

 

[bluedempsey]

or would it act like live rock
i know not like totally live*saltwater live*

 

[Vince]

My neighbor who has a pond made a makeshift 50 gallon trashcan, with a powerful pump pushing 3000 gallons an hour into the bucket full of quarter sized lava rocks. The problem we encountered is since it is an outside pond, the algae buildup was out of control, and the algae attaches to the rocks and somewhat clogs the aeration into the "holes". My guess is if the algae in under control, lava rocks should work better than your typical bio-media. Plus I think it would also hold more bacteria because of the porous material vs. the plastic ones. Let us know what you decide on...

 

[Stella]

Any surface can provide a place for good bacteria to grow. There will even be some on the tank glass.

Laura

 

[bluedempsey]

something like this *sorry for crappy drawing*

 

[Vince]

Oh, so that would be in addition to the bio media. It should work as long as there is oxygen flow into the rocks.

 

[bluedempsey]

Oh, so that would be in addition to the bio media. It should work as long as there is oxygen flow into the rocks.

thats what i was thinkin!

 

[Oddball]

With all of your media under water it is no longer considered a wet/dry filter. Setting a proper w/d with media above and below water will allow the system to perform more degassing (water stripping through increased water to air contact). The use of crushed lava rock isn't a new concept. It's exactly what we used before the invention of bio-balls and other similar products (also used broken adobe bricks). The big deal with the new bio-media was that it would not alter pH as lava rock will. And, lava rock also increases trace metals in your system. In fact, when bio-balls were first introduced they were so expensive that fish mags would run articles on alternate media for wet/dry applications. My favorite one (and one that I used for years) was to use those green plastic toy soldiers. Lots of surface area on these toys with all the weapons, uniform gear, etc.