wet dry.

Ok so i have a wet/dry filter. took out the bio balls. it has a dripplate so the water goes thru the holes over the whole box. my question is if you put rock in there to seed it, will it be come a nitrate factory like the bioballs?. the water just washes over the rock down to the sump. if so how long do you think it will take? is this good or bad idea? oh and the rock is utah rock washed and sprayed clean.
thanxs
Brian

Edited by peregrinus

I second that. The rock will have the same effect as the bio balls.

Is the rock going to be submerged or would it be up in the air for the water to drip over it? It must be submerged to do it's job.

The reason that bioballs become a so-called "nitrate factory" is because the surfaces where the bacteria live is in immediate contact with aerated water. This situation is great for ammonia and nitrite conversion but lousy for eliminating nitrates. The nitrate eating bacteria need to be in places where oxygen is low. Low oxygen areas occur in the holes and interior of the rock.

Low oxygen areas are also in the depths of substrate. That's why the proper depth of substrate is so important. Down below 1-3 inches, depending on particle size, oxygen is low. In low oxygen areas, nitrate is changed to nitrogen gas and other molecules/compounds containing oxygen and nitrogen.

We have discovered that there is ample ability for the average aquarium to handle ammonia and nitrites without the trickle/wet-dry/bioballs. The reason hobbyists can now grow coral so well and keep fish and inverts alive so much better, is because they advanced from the trickle method in favor of the deeper substrate and LR method.

Does this help?

Edited by Mark Peterson