cant keep NO3 level down. pls help

[petchong]

Tank : 4ft x 2.5ft x 2.5ft

Sump : 3 ft x 1.5ft x1.5 ft ( 4 compartment) 3 com with coral chips

4in sand bed

25 kg live rock

over flow with bi-ball

de-nitrator

skimmer

Fish : 2 2.5in regal tangs , 1 2in purple tang , 1 2.5 in bi-color angel , 1 2 in flame angel , 1 2in lemeon peel angel , 1 2 in coral beauty , 1 2in clark crown , 1 2in cleaner wrasse , 1 2in royal dottyback , 2 cleaner shrimp , 1 boxing shrimp.

Coral : around 15 pcs of hard coral ( not very sure of their name)

water change is kept at 15percent every 2 weeks. NO3 level is around 25. how can I lower the No3?

BTW is it true that UV light should not be used?

[AhLoon]

Hi petchong,

I don't think UV light has got anything to do with NO3 level.

[LIM CHYE HUAT]

coral chips and the bio balls.

[monsterz1975]

What brand of denitractor u using?

[monsterz1975]

25kg of LR for a 4x2.5x2.5 tank?

[RAV-65]

too little rocks... try using a small pump to blow at your rocks... r there lots of detritus buildup? The bioballs and coral chips got lots of detritus buildup?

[subxero]

What brand of denitractor u using?

Hee Hee.. you going to introduce AquaMedic Denitrator?

[roidan]

1) You can try removing the coral chips/bioballs

2) Add more cured live rocks

3) Tune your existing denitrator properly

4) Tune your skimmer properly / Get a better skimmer

5) Lower your number of fishes / Feed them less often

6) Change water once a week instead of twice a week

7) Change a larger percentage of water instead of your 15% each time

8) Ensure the water for your salt mixing does not have significant nitrates.

You can use DI/RO to absorb nitrates from your water source.

UV light does not significantly increase NO3.

U can try a combination of the above to tackle your NO3 problem.

[scarab]

First and foremost, you must get rid of your bio balls and corals chips. These are major nitrate factories as they are very efficient in the ANN cycle. This is due to the fact that they have large surface area for bacteria to colonise hence they convert Ammonia to Nitrite to Nitrate very fast.

Then follow what roidan has posted, you should be ok. Also if possible, increase the flow in your tank to prevent dead spot as they collect detritus which will also eventually contribute to your nitrate.

[stabilo]

Just curious....I read somewhere in SRC that our tap water got some trace of nitrates? Izit true?

Think I gona do some test....

[Awgui]

I am wondering if u were to take out entirely the bio balls and coral chips, wouldnt then ammonium be high though nitrate could be low? and isnt it that ammonium is more "toxic" ??

[roidan]

The way to removal is to do it slowly and gradually to allow the system to catch up.

*topic moved from LPS forum to General Reefkeeping*

[scarab]

Yup, can remove is stages so as not to cause ammonia spike.

[Jimng]

I am wondering if u were to take out entirely the bio balls and coral chips, wouldnt then ammonium be high though nitrate could be low? and isnt it that ammonium is more "toxic" ??

That's where proficient Protein Skimming comes into play.....

[Awgui]

In the long run, if I have considerably large ammount of live rocks in the tank itself and a relatively large deep sandbed, there should be enough surfaces for aerobic bacteria to grow and thus do not need the bio balls and coral chips rite?

By the way would a macro as300 be considered as sufficient for a 4ft tank?

[FuEl]

Hmmm...lower your fish load. That would certainly help. But then again don't be overly worried. 25 ppm of nitrates won't really kill anything. Levels toxic to fishes are way above 100 ppm. Most corals even sps can withstand 25 ppm of nitrates rather well without much side effects. Just try not to let levels climb over this level for more sensitive corals. The only things I could think of that 25 ppm of nitrates would have effect on would be fish larvae and maybe bivalve/crustacean larvae which are far more sensitive than most aquarium livestock. But then again it does'nt hurt to lower your nitrate levels if you are overly cautious like most reefers. Just bear in mind that there has'nt been much literature or proof of nitrate toxicity in such low amounts.

In all cases, just make sure your test kit is working. If not your worries might have been for naught.

[madmac]

Well said, couldn't agree more with you, FuEl.

25 ppm would will brown SPS corals...

Hv your media cleaned regularly(monthly), it works well to reduce your ammonium... then I would reduce feeding. Think of it this way. If you reduce your ammonium, your nitrite would be lower, your NO3 would be lower... otherwise, so long as the source is there, changing your media won't help for long. Try for 1 feeding every two days, you fish won't die of starvation.

[Kelmen]

If you have a refugium or spare compartment, culture macroalgae.

Or if nothing in your main tank interested in greenery for food, grow some inside there.

Grow more light-loving organism (coral) may help too.