Extremely frustrated, can't lower nitrates on established reef. Massive water changes, bacteria supplement, carbon dosing, chaeto...NOTHING WORKS!

[2Wheelsonly]

I have an established reef about 4 years old. Primarily SPS; about 2 months ago I had a nitrate spike of about 60 after I used Vibrant to get rid of some hair algae in tough spots (it killed algae within my two week dose of 30ml once per week). I typically run the tank anywhere from 5-10.

Nothing has really changed; I never did major water changes in the past. My livestock is fairly low for a 300G tank. 96x30x24

Livestock: 3 yellow tank, 1 sailfin tang, 1 blue tang, 1 powder blue, 2 clown, 1 anthias, 1 diamond goby, 1 green wrasse, 1 melanaurus. (No fish death in the last 2 years, ammonia is 0/nitrites are 0)
Skimmer: Lifereef oversized 36 inch rated for 400-600
Salt: instant ocean with 5 stage RODI. Water tests 0 no3.
P04: 0.05 according to hanna ULR and 0 according to salifert (junk/useless)

I have tried vinegar dosing, currently been using 50ml of nopx every day for the last month and it has done NOTHING. At this point I am so desperate I don't care if I wipe my tank and tried using AZ-NO3 and nothing. I am also dosing 50ml of microbacter7 daily. Chaeto in my algae reactor is not growing at all and starting to die.

I have always vacuumed my sand bed daily; it's only 1.5 inches at best and I have tons of rock in the tank.

Over the last two weeks I have changed out over 500G of water doing 50-100G a day and nitrates are still 50+. Has my tank reached the age where it's just destined to die? I am tooth grind mad right now over this crap.

 

[siggy]

Did you try a new test kit?

 

[TheShrimpNibbler]

I would stop with the nopox. Also, I wouldn’t vacuum the sand bed daily. A very large amount of denitrifying bacteria live there, and vacuuming sucks some of them up. Definitely run carbon. Other than that, just stop messing with things so much would be my advice. Keep things stable and things will stabilize themselves. Additives only lead to problems in so many cases.

 

[2Wheelsonly]

Did you try a new test kit?

Yes I did, I also have a frag tank and a smaller clown tank. The test kit seems accurate. I also used two to check against each other (salifert and redsea pro).

 

[wtac]

Sulphur Reactor. It will take about 1-2 weeks to adjust and dial in 0 effluent and about 1-2 months to get NO3 down to where you want it.

You can get a dual chamber where the secondary chamber is filled with aragonite to buffer up the pH or single chamber have the effluent drip into a tall narrow vessel filled with aragonite with holes at the bottom.

 

[ScottB]

Did you try a new test kit?

+1 I'd be suspicious of the test being bad. What kit?

*edit*

I see you answered that already. Baffling.

 

[Reefasaurus X]

I was in your same situation with my 25 year old 80 gallon reef. Water changes, Chaeto refugium, vodka dosing.. and nitrate would not go below 50. I put some Algone packets in a high flow area of the sump. Changed them weekly for 5 weeks. By week 5 my nitrate was down to 5ppm and sps happy colorful and growing again. So get some Algone. It’s relatively cheap and easy. Now I keep two packets in the sump and change them monthly. Easy peezy.

 

[2Wheelsonly]

One other thing i'll add: Ever since my no3 issues came about, my pH is really high. I normally run pH 7.8-8.0 and it's been 8.38-8.1. I thought my probe was off and recalibrated, I also plugged a brand new lab grade prob from my frag tank's apex and it verified the correct reading.

Not sure what's causing pH to be so high but it seems to be related.

 

[ca1ore]

That is odd, I agree. Though not without some disadvantages (namely alk depletion) I’d second a sulfur reactor. Somewhat out of fashion these days, nothing I’ve found destroys nitrates quite so well.

Might want to post in the chemistry section. Perhaps there’s something amiss that RHF would have a useful perspective on.

 

[2Wheelsonly]

I'm still not sold on my po4 testing, earlier this morning my hanna says 0.05 po4 and now it says 4pbb which is 0.0010 (very low). I tested 3 times and it's 4, 7, 4, 3.

Since my nitrates are so high could my po4 being so low that bacteria can't break down the nitrates? I also have 0 algae visible in the tank, other than cyano my rocks and sad are perfectly clean (as are the tank walls). I would think i'd have algae problems with these nitrate readings. My coral colors are so dull.

 

[Nano sapiens]

Had a similar issue with NO3 jumping to 50 - 60 ppm in a very mature nano due to too many fish and resulting high nutrients. In these cases, I aggressively start removing all the crud that has collected in the sand bed and especially under the rock work. If you can't remove most of the rock, then use a turkey baster or small powerhead with an attached tube to get underneath and do it in sections over the course of a month or so. My NO3 dropped to 10 ppm in about a month and has slowly continued down to 6 ppm two months later.

 

[ZoWhat]

How old is your LR?

NO3 can get absorbed into your LR and the only solution is to manually remove the LR and SWISH SWOOSH it in a bucket of RODI

 

[2Wheelsonly]

How old is your LR?

NO3 can get absorbed into your LR and the only solution is to manually remove the LR and SWISH SWOOSH it in a bucket of RODI

Everything I read including some of the more scientifically oriented folks like Randy-Holmes-Farley have said nitrates can only exist in water column and can't be absorbed by rock. Are you confusing this with po4? Po4 can be absorbed by rocks and leach out but from what I understand, no3 can't.

 

[HB AL]

I have a 90G heavily stocked fish and coral system of mostly Acros and add 10ml one day and 20ml the next of red Sea nopox doing this every other day to keep my nitrates under 10. I would up your dose of carbon dosing.

 

[ZoWhat]

Everything I read including some of the more scientifically oriented folks like Randy-Holmes-Farley have said nitrates can only exist in water column and can't be absorbed by rock. Are you confusing this with po4? Po4 can be absorbed by rocks and leach out but from what I understand, no3 can't.

I really meant your LR might have absorbed excess nutrients that FEED no3

 

[theMeat]

Everything I read including some of the more scientifically oriented folks like Randy-Holmes-Farley have said nitrates can only exist in water column and can't be absorbed by rock. Are you confusing this with po4? Po4 can be absorbed by rocks and leach out but from what I understand, no3 can't.

Not about to argue with Randy Holmes. In my experience nitrates can saturate and have a “bank”. Don’t know if that’s the rock itself or what does and does not grow on it.
Have seen this ‘old tank syndrome’ of sorts on many tanks.
Pick a method and stick to it. If it’s carbon dosing you really need to commit to a schedule and stick to it or you won’t see much if any progress.

 

[Dennis Cartier]

Ok, I have been in a similar position before. When you mentioned your corals are pale, that was the last item on the checklist for nutrient limitation. You have a limitation on an element that your corals, algae and in this case carbon dosing require for natural biologic processes. You have mentioned that your PO4 is very low, so that could be the limitation. In my case, it was Iron limiting nitrate and phosphate uptake due to lots of cheato growth. My corals were paling out and dieing, cheato was not growing and I had super high nitrate (50 ppm) and phosphate (0.15). I dosed a bit of iron and the corals coloured up and cheato started growing again. You just need to figure out what is limiting you in your case. My bet is on iron or phosphate.

Oh and for iron, a little goes a long way. You can't overdose it, but it will brownout your corals in the presence of high nitrate (which you have). So if you try it, just a bit at first to confirm, and then slow and steady if you continue.

Dennis

 

[wtac]

So when you do a water change, NO3 will diffuse or leach out from the LR...like a tea bag, the second time you refill your pot of tea, you still get the tannins (NO3 analogy) but the color is a tad lighter. Repeating the process you will notice the color getting lighter until at some point, you wont get any more tannins from the tea bag.

Not to contradict Dr Farley as he is correct that NO3 does not bind to anything as NO3 salts are highly soluble but what he does not address is the porosity of LR and diffusion.

Take a chunk of LR from the inner rockwork that has no growth. Rinse with water from the aquarium to remove all the detritus. Put in a vessel of NSW, let it sit for a day and then put into another vessel of NSW for another day. Test the waters and you will get a reading for NO3

 

[LC8Sumi]

I’m 99% sure you can’t lower it because your PO4 is super low. It sounds counterintuitive, but dose phosphates, and the nopox will then lower the nitrates super fast. That said, if you manage to get the PO4 up to around 0.15-0.2, chances are your tank will look way too healthy for you to want to lower the values ever again

 

[Dennis Cartier]

So when you do a water change, NO3 will diffuse or leach out from the LR...like a tea bag, the second time you refill your pot of tea, you still get the tannins (NO3 analogy) but the color is a tad lighter. Repeating the process you will notice the color getting lighter until at some point, you wont get any more tannins from the tea bag.

Not to contradict Dr Farley as he is correct that NO3 does not bind to anything as NO3 salts are highly soluble but what he does not address is the porosity of LR and diffusion.

Take a chunk of LR from the inner rockwork that has no growth. Rinse with water from the aquarium to remove all the detritus. Put in a vessel of NSW, let it sit for a day and then put into another vessel of NSW for another day. Test the waters and you will get a reading for NO3

I totally disagree with this analogy. The only thing you need to worry about is dilution, not diffusion, unless you are doing a 100% water change. The fact of the matter is that water changes take many large changes to have a big impact on severely elevated readings. Implementing daily automated water changes will eventually lower elevated readings over time.

Dennis