Nitrates

[rob s.]

Hello all, I have recently been battling a high nitrate level (40/60ppm) in my tank. All other parameters are good and i have been dosing nopox with little results. I learned that if there is no to very little phosphates the nopox does not work. I'm not sure on why and also don't quite understand why a large water change can cause the nitrates to sky rocket. I do a weekly 5 gallon change which is close to 1/3 of my 20 gallon tank if you take the rock space into account also. Does to big a change at once actually hurt the nitrifying bacterias that consume the nitrates? If so then this was/is my problem but it seems like a double edged sword. If i don't do water changes in such a small sytem my parameters constantly waiver which is not a good enviorment for my torches. They have refused to fully extend for about a month now Anyone got some advice or experience to pass along as to getting things back to normal. A happy tank equals a happy torch and i want my torches happy.... Thanks

 

[AmaleeC]

Every tank is different so the nopox may not work as well for you as it has others. :/

How long has yours been set up? Please share your other water parameters as well.

Maybe you can get away with less frequent water changes. It is also possible that the RODI water or the salt you use when mixing your water has high nitrates.

 

[rob s.]

tanks about 10 months old. salinity 1.025, Ca 420 0amonia, 0nitrites, almost 0 on the phosphates and my DK was about110 I run an ai prime light, turkey baste a lot have great growth of coralline taking hold and a good CUC

 

[rob s.]

tanks about 10 months old. salinity 1.025, Ca 420 0amonia, 0nitrites, almost 0 on the phosphates and my DK was about110 I run an ai prime light, turkey baste a lot have great growth of coralline taking hold and a good CUC

i only feed every other day and i only have 2 clowns and a grama. All my hammers look great and are growing new heads my zoas look real good and are also growing. My acan has about 6 or 7 new polyps and my porites is also growing nicely

 

[AmaleeC]

Okay. I’ll wait for the more advanced reefers to chime in. But have you checked your RODI or freshly mixed saltwater?

Sometimes coral foods offset the balance in phos/nitrates. Are you using RODI water?
If it’s just your torches, check for pests and check to see if any fish are bothering them.

 

[Crustaceon]

The main issue is the lack of phosphates. Bacteria needs it in order to consume nitrates in ratio. IME, you won’t see a nitrate reduction through normal denitrification under a .02ppm phosphate level. I’ve been through the exact same scenario before with 20ppm nitrates/ near zero phosphates and had to manually dose phosphate daily to slightly elevate levels (.08ppm). I also added some distilled vinegar (5ml to a 65 gallon system). This caused a light bacterial bloom and reduced both nitrates and phosphates. My skimmer cup smelled disgusting. I repeated this process for a week and ended up around 10ppm nitrates.

 

[NeverlosT]

can you run a refugium with Chaeto and dose Brightwells ChaetoGro once a week? That did wonders for my nitrate levels when other measures failed. Chaeto also requires more nitrate then phosphate so it might be a good solution here.

 

[Hincapiej4]

You could be stripping the water of amino acids. Try dosing some reef energy or fuel and see if it helps. Also, feed more to bring up your phos to help.

 

[Hincapiej4]

I run a refuge on my xl300, phos been stable at somewhere between .08 - .12 whenever I check it and always at 10 nitrate.

Try the natural approach if you can first.

 

[rusgum]

Phosphates are the key to your problem. No matter how much carbon you dose, if the bacteria lack phosphate, then the nitrate cannot be reduced.

 

[SPR1968]

To be honest the easiest way to control nitrates in a system of that size is by simple water changes

As you’ve been doing this I would make sure your using 0 TDS RODI water to make any new saltwater as the water quality could easily be the issue. In theory if you do a 25% water change nitrates will drop by roughly that amount ot thereabouts. If your buying it ready made up for you, you really need to check the quality.

As you mentioned, large water changes can upset the stability of the system, hence the 10% guideline, so you could maybe do a series of 10% changes say every other day and see how that works.

Also you don’t mention if your adding coral foods, but that can increase nutrients especially if you use it everyday. I use reef energy and reef roids once every 2 weeks and that’s it.

You don’t need to worry about the bacteria, most if it’s in the rockwork

You could continue with nopox, you only need a tiny amount of phosphate, but you also need to ‘wet skim’ for it to work effectively. When it’s at peak performance the nopox skim should be like a ‘light tea’ colour. I use nopox in my S650 but I also use rowaphos to keep phosphate down. Just increase the dose as per the instructions until nitrate starts to drop

 

[rob s.]

To be honest the easiest way to control nitrates in a system of that size is by simple water changes

As you’ve been doing this I would make sure your using 0 TDS RODI water to make any new saltwater as the water quality could easily be the issue. In theory if you do a 25% water change nitrates will drop by roughly that amount ot thereabouts. If your buying it ready made up for you, you really need to check the quality.

As you mentioned, large water changes can upset the stability of the system, hence the 10% guideline, so you could maybe do a series of 10% changes say every other day and see how that works.

Also you don’t mention if your adding coral foods, but that can increase nutrients especially if you use it everyday. I use reef energy and reef roids once every 2 weeks and that’s it.

You don’t need to worry about the bacteria, most if it’s in the rockwork

You could continue with nopox, you only need a tiny amount of phosphate, but you also need to ‘wet skim’ for it to work effectively. When it’s at peak performance the nopox skim should be like a ‘light tea’ colour. I use nopox in my S650 but I also use rowaphos to keep phosphate down. Just increase the dose as per the instructions until nitrate starts to drop

thanks man that some helpful info!

 

[ReefLab]

Another vote for phosphates. I had about 10ppm nitrate and 0 phosphates for about 2 months. Many of my corals died.

I’ve started feeding heavier and even dosing phosphate to maintain a minimum of .03 up to .1. My tank looks much better and polyp extension is great.

I would stop dosing Nopox (it’s basically just vodka aka ethanol aka carbon dosing) and monitor phosphate. Nitrate will slowly come down as phosphate is consumed by your corals/algae.

 

[excell007]

If I understand the nitrification process correctly, bacterias do not consume nitrate. Bacterias will consume amonia to become nitrite and another form of bacteria will consume nitrite producing nitrate. Nitrate is then removed thru nutrient export, like water change/skimmer/refugium/scrubber and others. Measure your tank right before the water change and a few minutes after when the new water have totally mixed up with the old water, if you did a 30% WC your nitrate should be reduced proportionately plus a few points cause your system is still producing it. If not, it means you have nitrate in your new water, measure it to be sure.

 

[Hincapiej4]

Nitrates are in fact able to be consumed by bacteria. But they are much more difficult to get established because they can only live where there is no oxygen.

 

[excell007]

you are absolutely correct, but like you said these bacterias that turns nitrates into nitrogen gas needs an anaerobic environment. So you need a de-nitrator to cultivate these bacterias, which for a 20 gallon tank, I think is an overkill. Regular water change from a source with 0 nitrate should be enough to control this. There are also some filter media, like seporax, claiming to be able to cultivate these bacterias by have having a very deep pores that oxygen can not penetrate, but I have not tried it.