Lowering High Nitrates

[nemofan]

My nitrates are at 40. I have a 92 gallon corner tank. How can I lower these realistically? I have a skimmer that I can't get to work. How much/many water changes do I have to do? I have taken to feeding flake every other day and frozen on the opposite days. Any ideas? Thanks a lot.
Anne

 

[mie]

Sounds like you are feeding way to much cut back to feeding two or three times a week. I would problably change 20 gallons a week till they are lower, (Someone may chime in with a different amount). What kind of skimmer do you have?

 

[coraljunky]

IMO. Change 20% of the water asap and repeat in 2 days. Definitely slow down with the feeding. How old is the tank?

 

[lexluethar]

Make sure you are changing the water with RO/DI and that the water you are changing with is testing zeros for AM, NI, NA. I would do 15% water changes every three days until you get it to around where you want it. Getting that skimmer to work properly will really help too.

 

[nemofan]

Thanks for your help. The tank was a year old this past September. The skimmer is a CU-75. I am using the suggested 300 gph pump and it fills the collection cup in about 10 minutes no matter what kind of setting I use. I set up this tank about a month ago combining my old 46 gallon tank with this new 92 gallon tank. At the time of setting it up the only fresh saltwater I used was about 20 gallons. I have about 100 pounds of LR in it also.
Anne

 

[mie]

So you empty the cup every 10 min or do you just turn it off?

 

[nemofan]

The skimmer troubleshooting did say that it can take 12 hours to start properly skimming. I have tried to just take and dump the collection cup but the bubbles/water still keep coming when it's on. I have also just unplugged it, emptied it and then plugged it back in and started all over. Won't it overflow? I have been just dumping the collected water back into the tank since it doesn't seem to be doing much. Thanks. Anne

 

[mie]

Sounds like somthing is out of adjustment. But i am not familiar with that skimmer.

 

[skipperdz]

do water changes...but your readings wont change overnight. it usually takes 4-5 days to show accurate readings after water changes. but when my trates are at 20 a 12 gallon change drops it in half. and i have a 55g
also get a refugium started, they eliminate nitrates and phosphates.

 

[nemofan]

Thanks for the responses. I have a crushed coral and some sand for the substrate, just out of curiosity do you disturb the crushed coral or just simply pull and replace the water? I'm so used to fresh where you mess the heck out of the gravel. If it really takes 4-5 days for an accurate reading I had done a 15 gallon water change the morning I had the water tested. So maybe they are lower? or just wishful thinking...........? Thanks. Anne

 

[skipperdz]

if you did a water change it should be lower...but to really know what it is youll have to wait a few days. see what it is then and if its not where u like it, do another water change
IMO i would get rid of crushed coral....thats one of your nitrate problems there, they arent as tight as sand can be so alot of waste can fall to the bottom of the tank and build up.
id remove and get more sand...adding sand wont cause a ammonia spike since you already have sand in there

 

[mie]

You do not disturb the sand bottom like you would on freshwater. You can skim the surface of the sand sucking up any matter on the bottom.

 

[nemofan]

I have sand in a bucket from my 46 gallon. Any easy way to suck out the coral and then add the sand?

 

[skipperdz]

unfortunately the only way i know of to remove crushed coral is to scoop it out. how long as the sand been sitting in a bucket? it its been a while there very well could be die off in the sand that can cause a spike in your tank.

 

[sly]

If your cup is filling up in 10 minutes then you have a problem...
Taken from another site

• Check the water outlet valve to ensure it is open.
• Check the bubble elimination sponge for clogs. If clogs are found, clean with running water and re-install for operation.
  Check the pump capacity
  Ensure water level does not exceed water level line label on the skimmer

One note on the crushed coral... if your substrate is deeper than an inch, it could be adding to your problem. I have kept crushed coral for 6 years with no problems (and no nitrates). I would remove any crushed coral that is deeper than an inch and make sure you have a sufficient clean up crew to handle the detritus. After that, it's virtually maintenance free. I haven't cleaned my tank bottom in years.
First I would fix your skimmer though. It's best to fix your known problems first than to guess at the unknown ones. Not having a working skimmer could be your problem all together.

 

[1journeyman]

Ok, a couple of points.
First, drop the flake food. Bang Guy has a good post I read somewhere about how quickly flake breaks down in the tank. Go with a variety of frozen foods. You may or may not be feeding too often, depending on what fish you have. Fish like Anthias and Chromis need more frequent feedings.
As for CC. You need to vaccuum it out, just like you would FW gravel. CC accumulates waste and adds to the Nitrate issue.

 

[mcbdz]

Originally Posted by NemoFan
I have sand in a bucket from my 46 gallon. Any easy way to suck out the coral and then add the sand?
The easiest way I have found to remove CC is to use your syphon hose. Take the bell end off the hose and it will suck the substrate right out of the tank. That is as long as it fits through the hose.

 

[nemofan]

Thanks for the help. I did another 15 gallon water change today and scooped out quite a bit of the crushed coral and thinned it out as best as I could. In order to get it all I'd have to remove all the live rock get it all out and start over.
What about the sand in the bucket? I'm sure that it is by now dead. It has been in the bucket for a few weeks in the basement. How do I go about getting it back into the tank without hurting anything.
Also, when would you suggest getting the water tested again since it could take a few days for the actual nitrates to be correct.
Thanks!

 

[bang guy]

Since Nitrates are a long term buildup and a long term reduction there's really no need to test for them more than once a week. Once they are stable once a month is all I would do.

 

[floridabob]

OK SORRY TO HIJACK THREAD BUT IM HAVING THE SAME
NITRATE PROBLEM ALSO., ALWAYS AROUND 60 -80 EVEN
AFTER A 20 GALLON WEEKLY WATER CHANGE
I ATTIBUTE IT TO HAVING A SUCKY SEACLONE SKIMMER.
I DO HAVE A HIGH BIO LOAD,10 ASSTD. CLOWNS 2 BANGI CARDS
AND 2 DOTTYBACKS. ASSORTED ZOOS AMD SHROOMS AND
ANEMONE
I FEED THE TANK PINCH IF CYCLOPEEZE AND FROZEN EVERY OTHER DAY
AND ORA PELLETS SMALL EVERY 3RD DAY
AND ONCE A WEEK NORI IN A CLIP
My Other Water Peram Are As Follows:
Salinity 1026
Ph 8.2
Nitrates 40 -80
Nitrites - 0
Ammonia .05
Calcium 390
Mag 1200 Trying To Raise
Phosphate 0.0
I DONT HAVE ANY HAIR OR CYNO IN TANK NOW (KISS OF DEATH)
JUST TRATES ARE VERRY HIGH
TANK AND REFUGIUM HAVE TOTAL OF 150 LBS LR
AND 150 LBS OF LS COMBINED ALSO GROWING CHEATO AND
MANGROVES IN REFUGIUM AND ALL GROWING OK
OTHER THAN A DIFFERENT SKIMMER IS THEIR ANY OTHER WAY OF REDUCING NITRATES THAT I HAVEDN LISTED
THANKS BOB