nitrate problem

[merlin0883]

Have a 55 gal with fair amount of coral and few fish. Huge wet dry filter and backpack skimmer. Can keep the nitrates below 40, but need to do water changes every 4 days to do so. I thought i had too many fish, but have been told this is not the problem. Have medium hippo tang, small lawnmower blenny, flame hawk, marine catfish, six line wrasse, and yellow head sleeper goby/sand sifter. Coral includes xenia, one open brain, small gorgonian, some zoa's and star polyps, black and red sun polyps, shrooms, finger leather, spagetti, and medium bubble tip anemone. I know people keep tanks with much more and keep the nitrates down. Have 2 large balls of spagetti macro algae. Any suggestions would be nice. would like the nitrates to stay below 10. thanks

[Bill S]

Merlin, try doing larger, less frequent water changes. In a 55, with what you have invested, salt is cheap.

Nitrates are a direct result of what goes in the tank. In other words, you may be feeding too much. How often do you feed, and how much? What are you feeding the BTA and how often. I RARELY feed my RBTAs (I currently have 7) - and only when they look really hungry. For instance, if you feed the anemone a silversides, it's kind of like having a fish die in your tank. Anemones are not particularly good at the digestion thing.

[erikharrison]

Check for detritus buildup in your wet/dry and rock work.

[JimD]

One thing is obvious to me, the BakPak skimmer, its not nearly efficient enough to handle the load, they are way over rated from the manufactuer. You might want to concider a larger skimmer... Another thing may be the sleeper goby, they disturb the sandbed and it releases whatever detritus that may be present and the skimmer cant handle the load so it just sinks back to the bottom and decays causing elevated nitrates and possibly ammonia... I doubt more water changes will remedy the situation >long term<.

[merlin0883]

Merlin, try doing larger, less frequent water changes. In a 55, with what you have invested, salt is cheap.

Nitrates are a direct result of what goes in the tank. In other words, you may be feeding too much. How often do you feed, and how much? What are you feeding the BTA and how often. I RARELY feed my RBTAs (I currently have 7) - and only when they look really hungry. For instance, if you feed the anemone a silversides, it's kind of like having a fish die in your tank. Anemones are not particularly good at the digestion thing.

i usually do about 40-50% water changes just to keep up with it. I recently did a 90% change. thought about doing 10-15 gallons at a time only for a while to see if that helps, but don't know if i will be able to keep up with it this way. even so, all of my coral looks great and are growing rapidly. maybe it's not even a problem. I feed the bta what i feed the coral--dt's, microvert, and target feed with brine, mysis, zooplan, and cyclop eeze. I feed the coral once a day, but something different each day--just rotate the food. about every 4-5 days I target feed the sun polyps, bta, and brain brine. the fish only get brine when i feed it to the coral. they eat all extra shrimp because it's been 4 days since they had some. otherwise, the fish eat minimal amounts of marine flakes and dried seaweed. oh, every saturday i give the brain 2 large frozen krill. no silversides. do you know at what ppm the nitrates would actually start to kill my coral? if you think of anything else, let me know. thanks

[merlin0883]

Check for detritus buildup in your wet/dry and rock work.

this is not a problem. the tank was moved about 3 months ago. i rinsed the filters with salt water and dipped the rocks in a bucket of saltwater and shook them vigorously. I hoped that this would remove most detritus while not harming too much bacteria with a freshwater bath.

[merlin0883]

One thing is obvious to me, the BakPak skimmer, its not nearly efficient enough to handle the load, they are way over rated from the manufactuer. You might want to concider a larger skimmer... Another thing may be the sleeper goby, they disturb the sandbed and it releases whatever detritus that may be present and the skimmer cant handle the load so it just sinks back to the bottom and decays causing elevated nitrates and possibly ammonia... I doubt more water changes will remedy the situation >long term<.

the skimmer seems to work well enough, but it can never hurt to upgrade, just in case. i got the goby simply because i thought he may stir the sand a little more and that some stuff would be sucked up instead of no stuff. maybe it was a mistake, i'm not sure. seemed like a good idea at the time. if anyone knows more on this, send it to me, please.

[matt]

You might be a good candidate for the "sand bed in a bucket" nitrate filter. Basically you fill a large bucket or tub with fine sand and circulate water slowly through it in a loop from your tank. There's a huge thread on reefcentral about it; it's a Calfo "invention."

[Troy Valentine]

Are you using tap water? If so check the Nitrate level in your tap water.
This could be your problem, in the past I ran into a similar situation, and it ended up being the tap water I was using.

Also you might want to check your Nitrate kit, many kits on the market will have you chasing shadows.

[erikharrison]

I did recently have a kit that went bad on me. It was registering nitrates higher than 160. Test your water BEFORE you put it in the tank to see if the kit itself is bad or if your water is high in trates. If it still reads high, take some water to a LFS and you will have a better idea of what is happening. Are you noticing any buildup whatsoever?