Nitrates won't go down!!!

[Twisted_blenny]

Ok my 55g tank has been setup for almost 9 months now and my nitrates are still thru the roof! They stay at 80ppm all the time. I do 10-15 gallon water changes weekly and still it never seems to go down? Plz any suggestions would help I'm at a loss right now

 

[chichimom79]

What kind of water are you using? What kind and how many fish do you have? How often and what do you feed?

 

[Zissou]

What's your filtration like? Are you using a skimmer/sump, canister filter, hang off back filter, etc?

What kind of substrate? Crushed coral or sand, and how old is it?

What kind of water? Conditioned tap water or RODI?

Are you using any bioballs or sponges in your filters?

Answer these questions and it'll be much easier to get help. :Cheers:

 

[Twisted_blenny]

What kind of water are you using? What kind and how many fish do you have? How often and what do you feed?

I have 2 clown, 1 dotty back, 1 six line , 1 goby I get my water from my LFS, and I only feed once a day of frozen mysis sometimes every other day

 

[Twisted_blenny]

What's your filtration like? Are you using a skimmer/sump, canister filter, hang off back filter, etc?

What kind of substrate? Crushed coral or sand, and how old is it?

What kind of water? Conditioned tap water or RODI?

Are you using any bioballs or sponges in your filters?

Answer these questions and it'll be much easier to get help. :Cheers:

Live sand, water from LFS no bioballs or sponges, I have a coralife protein skimmer but using it as a hang on because I don't have a sump yet and just my 70lbs of my liverock

 

[Kelz88]

Do you test the waterchange water?

 

[Twisted_blenny]

Do you test the waterchange water?

Yup and it goes down a tiny bit but by the next day it's right back up

 

[Kelz88]

I mean the water you do the changes with, is it 0 nitrates?

 

[Twisted_blenny]

I mean the water you do the changes with, is it 0 nitrates?

Ya I always test it and its always 0

 

[FishyReef]

What kind of test kit are you using? Have you taken a water sample to your LFS to have them test it independently? Have you ever had a problem with hair algae, cyano, or other algaes?

 

[Steveg229]

What do you have for powerheads and what kind of clean up crew do you have? Has anything gone "missing" in your tank since startup?

 

[FishyReef]

Another question beyond what I already posted - What type of rocks do you have? Were any of them called river rocks or do any of them look like lava rocks?

 

[bjohanson1234]

Well, it is possible that you have a lot of nitrates locked up in your rock work and sand. I would reccomend cutting back on feeding to half as much as you are. Continue your weekly water changes, and if possible, up it to 20 gallons a week.

Just to do the math, 10-15 gallons a week on a 55 gallon is about a 20% water change, you are only taking out 20% of the nitrates. So 20% of 80ppm is 16ppm. You nitrates right after a water change will be about 64ppm. The nitrates trapped in your rocks and sand start leaching back out into your water since the water has a lower concentration than they do. This is what is bringing them back up.

Coupled with over feeding, something MANY hobbyists do without even knowing it, you nitrates can easily be back up to 80ppm in a few days.

The key here is to only feed sparingly, have a good clean up crew, and maintain water changes.

If you can balance this out, the nitrates will start to go down over the course of a few months. Not days or weeks.

 

[Twisted_blenny]

What kind of test kit are you using? Have you taken a water sample to your LFS to have them test it independently? Have you ever had a problem with hair algae, cyano, or other algaes?

I'm using the API test kit, took it to the lfs and they tested the same thing I haven't had any algae or cyano problems

 

[Twisted_blenny]

What do you have for powerheads and what kind of clean up crew do you have? Has anything gone "missing" in your tank since startup?

I've got two hydro koralia 750 and I have an assorted mix of crabs and snails. And I don't think anything has gone missing

 

[Twisted_blenny]

Another question beyond what I already posted - What type of rocks do you have? Were any of them called river rocks or do any of them look like lava rocks?

I have pukani dry rock from bulk reef supply

 

[FishyReef]

So it sounds like it isn't a bad test kit or the rock. Hmm. I'm kind of out of ideas since it doesn't sound like the usual suspects (source water, overstocking, etc). The only idea I really have is that pukani rock is super porous and therefore can hold a lot of detritus in it, building up nitrates over time. Your brand of skimmer isn't a very effective skimmer so I suspect you have a lot of extra solid material floating in your water column. Combine that with really porous rock that can hold detritus and that is probably where your nitrates are coming. But I'm not at all suggesting replacing your rock - pukani is awesome rock and gives great surface area for bacteria to grow. You might want to invest in a better skimmer though. Another thought would be to get a hang on back filter, remove all of the media, and put some chaeto in it to tumble and put a small clip on light over it to give it light. Macro algae will help consume nitrates. You could also get some different types of macro algae to grow in your tank rather than doing a HOB filter converted to a refugium. Beyond continuing to feed only sparingly (and for 4 fish I think 1/2 cube every other day would be plenty), increasing your cuc to eat detritus and left over food, and continuing with decent and regular water changes, there isn't much else you could do. Some people have had luck with biopellet reactors, others haven't. You could research those more and see if that might be an option.

 

[noy]

Actually its not that suprising your nitrates are high. The system that you have has no means of exporting nitrates which are at the end of the nitrogen cycle.
Filtration and the Nitrogen Cycle, by Les Pearce
The normal bacteria buildup in tanks only breaks down ammonia and nitrates into nitrates. Obviously your water changes are not exporting enough nitrates and your tank has been in a high nitrate environment for a while so your rock and sand probably has a fair amount of nitrates locked in.
Even normal feeding will cause nitrates to increase and if you import through normal fish waste is higher than your export - you nitrates will go up and up and up.... From what you are saying it doesn't sound like you are overfeeding. I feed my fish 3x a day.

To bring Nitrates down you need some means to reduce nitrates you may want to think about:

1) Running an absorbent agent like Purigen from Seachem. There are lots of these on the market. I find Purigen is good for smaller tanks onlly - yours (55g) is close to the limit. Start with the small pre-packaged size. This stuff is messy to handle if you are using your own filter bags.

2) Run a refugium with macroalgae. The plants will consume the nitrates and help with the export. You can even get a small HOB refugium if you don't want to bother with a sump. Mangrove plants work too but I don't find them that effective. This is probably the best solution long term.

3) I don't recommend this for you but you can promote anerobic bacteria growth through carbon dosing and biopellets. If you are not careful you can crash your tank with these methods.

If the nitrates are not bothering your fish (they are healthy, eating and active) or corals (probably slow growth at 80ppm but not harm them) - just take you time with whatever solution you want to pursue. You probably do more harm with sudden enviornmental changes.

 

[mariobrothersleeve]

I dont believe anything is obvious. Did you open up your rock work? Try a different pellet food. Frozen foods have alot of different elements in them too. Well be here, just keep it slow too, to much change at 1 time is bad. I change 5 gallons everyother day, sometimes more frequent water changes help too. What are your phosphates?