Activated Carbon Q's

[erick]

I would remove all those blue bio'hazards' and replace with live rock, but not to exceed the water level in the sump. At least in the very bottom where you have floating balls.

[NaCl_H2O]

Bio-balls, Stars, Live Rock - it's all the same - simply surface area for bacteria. Probs with W/D filters is the filterpad - you want to change tha pad often enough (exporting nutrients) so they can't get into the nitrogen cycle. Bio-balls are not a nitrate factory, well ok they are, but they are suposed to be! Ammonia - Nitrite - Nitrate. If you have a bio-load (anything living) you eventually get Nitrates if all is working ok. Nitrates are the least toxic, and they are handled only by a good fuge, or a DSB, or somewhat poorly by water changes.

Your size tank (47g) probably doesn't need a wet dry, the LR and mechanical filtration should be enough - but your skimmer (if that was a skimmer in the pic?) is probably inadequate. I have about 40g of Bioballs in a huge Wet/Dry in my system, and a huge skimmer, and a 60g fuge, and, and ...

Leave the Bio-Balls or take them out, really doesn't matter, just don't leave waste in the mechanical filter without changing once a week or so - important thing is to test for a stable nitrogen cycle. Once stable for 6+ months the system can pretty much be trusted to maintain itself - just watch for signs of instability.

Carbon - I have a huge bag in my sump 24/7 - change it when I remember and have it on hand - probably 30-90 days. Carbon is an insurance policy - it will quickly absorb toxins released from tank inhabitants and scrubs the water for clarity.