Consistantly high nitrates

[chad316]

I am still fairly new to the hobby ~1 year. My tank as been up for about that long, but unfortunately I ran into trouble before running into this site. Essentially what happened was I added a "miracle potion," and miraculously everything disappeared. My tank went through a huge cycle (eg. +5 ppm ammonia) about three months ago. So even though this tank has been up for about a year, the major cycle essentially reset the maturity of my tank. After the tank finished the cycling, I started adding green chromis one at a time every two weeks. (up to 4 now)

Now for the last few weeks I have had ~20 ppm of nitrates even after doing 10% water changes per week. Actually, once I saw my nitrates were at this level I have done 20% water changes with no difference.

At this point, I suppose I need advice to get my nitrates down. I have a skimmer producing dark green skimmate...seems to be working fine. Also, I feed the cromis 1/3 cube of hakari mysis morning noon and night (1 cube total per day) Carbon and GFO reactors and using RO/DI water with TDS meter reading 0 conductivity. Canister filter...not sump or refuge

I am trying not to stir up the sand bed, but could not sifting the sand effect the nitrates that much? Since the cycle was so large (~5 ppm ammonia), is the bacteria simply devouring everything and leaving nitrates? Any ideas? Thanks, in advance.

[Sk8r]

It's your cannister filter. Your sandbed should not be disturbed ever, except getting some nassarius snails, about 3, to tend it. Marine reefs don't use filters because their processing goes to nitrate---and stops there. Start removing layers of media from the cannister---a little bit every 3 days, and replace it with live rock rubble and you should see an improvement as you go.

[chad316]

@Sk8r Thanks for your quick response. I do have live rock rubble in my canister, but it also has various sponge medias as well. You are saying just use the rock, and take out the sponge biomedia one per three days whilst adding more rubble? I just want to be sure I am clear on that one Also, I have 3 large nassarius snails and 1 small one as well in my DSB.

[aes]

I agree. But keep doing the weekly water changes also and you will soon start seeing an improvement

[Sk8r]

YOu should be on your way to improvement, with the gradual removal of those sponges. COrals will happily eat the detritus. Use them as your filter, particularly if you have no sump.