High Nitrates

If your using Bio balls I'd swap out 25% each week and replace with LR rubble.

 

Water changes are not that useful for reducing nitrates. You need to figure out why the nitrates are high and remove the source. Could be water coming in, detritus build up, over-feeding, under-skimming, not enough LR etc... I would sort of go in that order. Check your top-off water, remove any detritus from substrate, filters etc... cut down on feeding a bit. Make sure your skimmer is clean and functioning. If that dosn't do it, you may need more denitrifying bacteria LR or deeper sand, remote DSB etc...

 

there isnt any in my DT but there is some in my sump and ive had the same salt since day 1 so i have a feeling its bad b/c its been up there since i started my tank but just recently started to get really bad.

 

just cleaned the skimmer fully yesterday when i emptied it, my top off water reads about 5ppm i just tested that today, i have about 80 lbs of live rock in my tank, no detritus in sand, only in sump i have a little, feeding, i use 1 frozen cube a day filter gets changed or cleaned every 2 weeks

 

Bio balls, and LR rubble is the same thing they both do the same purpose

 

By the way. Nitrate itself isn't not toxic. You can have 200ppm+ with little detrimental direct effect. The issue is two-fold. 1st is algae outbreaks. This is more likely if nitrates are high. The second possibility is that the symbiotic algae in your corals may be able to proliferate and this can stress corals. There isn't much info on how high becomes a problem in this regard though.

 

Not true. bio balls will not reduce nitrates - but to acheive nitrification the rubble must be under water

 

I think I asked if there was an algae issue but it might have went unanswered. My thought process was faulty test kits if not.....

 

if it were my tank i would beef up the sand bed and beef up my cuc..and then buy a phosban reactor and get rid of those bio balls

 

I've discussed this with many times with experts such as Randy and the general consensus seems to be that LR rubble does not provide any significant de-nitrification. The pores just are not deep enough. So, I agree they are mostly the same. Bio-balls may be slightly worse though actually because if water is trickling over them the increased O2 makes them more efficient at nitrification and out competes the LR for denitrification. This may be an issue for the reason described below.

Bio-balls and LR rubble are detritus magnets and seem to be associated with nitrate problems. They also seems to be associated with nitrate problems, even when detritus isn't an issue though. So, to explain this, some people, including Randy Holmes-Farely have suggested that denitrification may need to take place in close proximity to nitrification to be effective. Bio-balls and LR rubble do not contribute to denitrification, therefore any nitrification taking place on this substrate is not in close proximity to denitrifying bacteria. Once nitrification needs are met, there does not seem to be any know benefit to using bio-balls or LR rubble instead of just LR, so, I would seriously consider just removing any LR rubble and/or bioballs.