If it was me, and I admit that I am not a fan of UGF
's, I would get rid of the UGF
. First, it's gonna suck all the trash in the tank down into the gravel bed where it will decompose and contribute to the nitrate problem. It will also, over time, clog up with mulm (leftovers from decomposed stuff) under the filter plate. The effects of this can be minimized by using a PH to reverse the flow through the filter plate so that it lifts trash off the substrate. The PH needs a sponge on it though so that it doesn't pump more stuff under the plate. Second, you will never have a working sand bed with the UGF
in place. I'm thinking crushed coral won't work for a deep sand bed anyway due to it's large size. In order for the DSB
to work, you have to have almost no water flowing through it so that the bacteria that convert nitrate to nitrogen gas can live. These bacteria require a hypoxic (very low O2
) environment. The lower areas of a DSB
provide these conditions.
Concerning the nitrite...are you sure it's 5.0 and not 0.5? 5.0 is pretty high. It sounds like your ammonia spike has come and gone and your tank is now experiencing the nitrite spike. That should diminish with time as the bacteria gets established. Water changes will help.
The high nitrate reading makes me suspect that nitrate is being introduced from an external source like the water or food. Have you checked the water you're using for nitrates? Are you feeding the fish every day? If so, I'd cut back on that for a while...maybe every other day and in smaller amounts. Even if you're using RO
water, and you should be for best results, check it for nitrates. Could be the RO
unit hasn't had a filter change in a while and it's performance could be degraded. JMHO