Nitrates in SPS Tank Help Please

chefmur · Dec 9, 2014

So I have been reef keeping for almost 8 years, started with a 45 gal , then a 75 and two years ago moved to a 150 mostly SPS tank. Everything was going great with fantastic color and growth on my SPS. I have a sump with a refugium on reverse light cycle with Cheoto algae growing, filter socks which I change every week and a large Vertex skimmer. I also run carbon and GFO , the carbon is changed out every month the GFO every six weeks. A 25 % water change is performed once a month.

A few weeks ago my SPS started to loose some color, then slowly over the last week I started losing SPS, they usually start dying at the tips I check my ALK, PHOS, CA, MG on a weekly basis and Have an Apex showing my PH. All parameters were in line and always fall around the following alk 8.3, CA 475, Phosphate 0.03, PH 7.8 night 8.2 day, MG 1350. I never check nitrates and never have since my tank cycle two years ago.

My radium LED have not changed so I knew it was not the lights, my fish, LPS and inverts are completely healthy so I ruled out any contaminant or copper poisoning.

I am pulling out my hair as I watch thousands of dollars in high end SPS wither before my eyes. I decided to have my buddy run some separate tests in case any of my test kits are corrupted or bad. He confirmed all the same readings as mine except NITRATE , he said it tested between 50-100. Holy crap I said I have never had a nitrate issue, I do not feed heavy I have about 8 fish, I do feed Oyster Fest and Reef Chili about three times a week, apart from a little bubble algae the tank is very clean. I do not clean or stir the sand bed when I do water changes and do not have any gobies or sand sifting fish , I do have a few snails that live in the sand bed and can see some layers of gunk in the bed which is only a couple inches deep, the top of the sand bed is clean.

My questions are What could be causing this ?
What can I do to get of it

Any help will be greatly appreciated, thanks in advance Mike

Randy Holmes-Farley · Dec 9, 2014

The cause (assuming the test is accurate) is more added than exported nitrogen.

The usual best answer is more export, either with organic carbon dosing, a denitrator, or more algae growth (macroalgae or ATS).

jcdeng · Dec 9, 2014

I think your sand bed is saturated and thats where the nitrate is coming from. Do you have any green film algae growing on the sand?

Cory · Dec 10, 2014

I had zero nitrates. Then I had 20ish ppm. Now I'm back to zero. I couldn't id where as I run a sand less aquatium. I found that the chaeto had a tremendous amount of food, poo and detritus in it upon shaking it out. After that, nitrates zero again.

Triggreef · Dec 10, 2014

I doubt nitrates would cause the sps deaths. I'd keep looking. Triton test perhaps

Wiz · Dec 11, 2014

In my last tank the nitrates always climbed up. It was the only parameter I couldn't tackle. Sps was the only coral type I couldn't keep. But in my current 40b I have tackled it and sps are growing. In conclusion it most likely is the nitrate. Destroy any pockets where you get build up and export more. If your sandbed is only a couple inchs, why not have sand sifters?

Chameleon · Dec 11, 2014

Hey bud,
Hope you can get this sorted out. I have a denitrator in the basement you are welcome to give a try. Maybe die off from the past is finally rearing its head. One option is incorporate remote deep sand beds. I am with you and dont test for nitrates anymore and doubt my kits are still any good. Let me know if you want to come by and get the denitrator.
-Tyler

Wiz · Dec 11, 2014

Denitrator? I bought some huge rectangle one years ago. Was like a lg canister filter. But all enclosed and super slow flow supposed to inject vodka. I followed instructions and got no result at all. After a year and a half I through the $240 pile of junk in the trash. I am convinced that a tank with no catch points for waste, a moderate to high flow, and lots of macros is the right way. These algae scrubbers look really interresting to. And cheap. If I hit a problem again I think ill try that.

Choptrucks · Dec 11, 2014

I've got an algae scrubber and it grows a lot of algae in a quick amount of time!! I honestly built mine for about 40 dollars including pump. You can build one for even less than that if you T into your return pump and put 2 grow lights on it. Like a livestock lamp from lowes and a good 3500k- 6500k light bulb. Grows the crap out of algae. And I also have a skimmer along side the scrubber

Randy Holmes-Farley · Dec 12, 2014

Wiz said:
Denitrator? I bought some huge rectangle one years ago. Was like a lg canister filter. But all enclosed and super slow flow supposed to inject vodka. I followed instructions and got no result at all. After a year and a half I through the $240 pile of junk in the trash.

There are two different types of denitrators. Sulfur based and carbon based. Yours was obviously carbon based.

Both can work well, but may be tedious to set correctly.

The sulfur types seems more preferred these days, but I'd guess that less than 5% of online reefers use either type currently.

sealbeach1 · Dec 12, 2014

When things start to go wrong I have found out the best thing I can do I send out my water to Aquarium Water testing in Colorado. If send on Monday I can have a full chemical analyzes on Thursday. It can be a real eye opener...