Should I add phosphate to help lower my nitrates?

[AbsoluteZer0273]

Ok, I’ve only been reefing for a little over a year, so please don’t kill me for this inquiry. I have a 180 gallon tank with a 75 gallon sump. It has been setup and running since last February. I cannot get my nitrates in check. I have done several large water changes. I have cheato that will grow a little then seem to die off. I don’t have any nuisance algae in my display tank although I have a few tangs and a foxface that could be keeping it at bay. I have a biopellet realtor with a little over a liter of pellets in it with a slow tumble, running for 6 months, and drains directly into my protein skimmer. I’ve tried nopox and prime. I have 200 gallon equivalent of purigen. My nitrates have been so high they maxed out on an api test at 160ppm. The lowest I’ve been able to get it is 50ppm by doing 50 gallon water changes 2 times a week. My phosphate has never been over 0.25 ppm. I recently came across the Redfield ratio which states photosynthetic biomass in the ocean uptakes 106:16:1 ratio of carbon: nitrogen: phosphate. I’ve tried feeding every other day. I feed less than a cube a day normally. With my phosphate always low, and the Redfield ratio interpreted as needing phosphate for the proper uptake of nitrogen(in this case the nitrate). Would adding phosphate used for a planted tank be a good resolution? I know this isn’t a new concept, but haven’t had any recommendations to do this. I think I know the original source was a fish that got lost in my rock structure about 2 months after setup. I fixed that problem right away by re-scaping my tank. And haven’t lost a fish since. Thanks in advance for any help!

 

[nautical_nathaniel]

I don't believe adding phosphates will solve your issues with nitrates, if anything it will provide another source of fuel for an impending algae outbreak. High nitrates is usually a result of a poorly cycled system, excessive feeding, or a combination of the two and a few other causes but it can usually be righted with time and small incremental changes to the whole system. When you cycled the tank did you add any beneficial bacteria supplements to it? Also, do you have a deep sand bed and if so does it get overturned/mixed around often?

The biggest thing I can suggest to you is try to make smaller changes to your aquarium, dosing this and that while adding stuff like bio-pellets to try and control nitrates is a synthetic approach to a natural problem and will upset the stability of your tank and usually cause more issues. While all of the products you mentioned do reduce nitrates in some way, they usually also affect some other aspect of water chemistry and can inhibit other processes from occurring. For instance, Prime can reduce nitrate and ammonia, but it also depletes oxygen and can reduce alkalinity as well due to the high sulfur content.

 

[tripdad]

I would add more biological means of reducing nitrates. You could add some Siporax in your sump or a reactor on very low flow. It will take a little while to have an effect but is very good at reducing nitrates. You could also look into adding bacteria if you feel you have enough rock but lack enough bacteria mass to combat the nitrates. There a few options there. Yes, you need some PO4 to remove NO3 but if you have some, as you say, then in my thoughts they would be bottomed out if this was the limiting factor. I would urge you to find the source first and reduce the input, that helps the most. Tangs and foxfaces are heavy waste producers by the way so you may need more space for bacteria to colonize to keep up, i.e. the Siporax.

 

[spiraling]

Excellent question. How are you measuring your phosphate? If it is 0.25 then there should be enough phosphate. If it is really 0, then adding might be helpful. Generally I've seen it the other way, phosphates are high and nitrates are low. In those cases it seems adding some nitrate does help reduce the phosphate.

Would adding phosphate used for a planted tank be a good resolution?

I have added Seachem Phosphorous to my tank to get the phosphate up from 0. It seems to be fine for reef tanks. There are other discussions in the chemistry forum on what to add. Like the other comments above I'm not sure it will help your problem. Generally for that high of nitrates its removal by water changes and other means. If a combination of biopellets, nopox, and chaeto aren't removing it you have a different issue introducing that much nitrate into the tank.

 

[AbsoluteZer0273]

Thanks nautical Nathaniel for the response! I did add beneficial bacteria originally with Aqua Bella. That didn’t seems to be working after 6 months and no help from them. I did get the ammonia and nitrite cycle, but nitrates never balanced out. I started mb7 dosing. I did the recommended dose of that for a few months with no improvement to my nitrates. I have and inch or 2 of sand in my display tank. I did have a deep sand bed in my refugium, but removed it after a recommendation from the lfs to do so. I also removed the bioballs a little while after for the same reason.That was a few months ago, and I have stoped dosing everything since. I do have the purigen still in the sump, but no other chemicals not even carbon. I started the water change regiment 10 weeks ago and that seemed to be helping. I just don’t think that much water is the final answer.

 

[spiraling]

You seem to have changed a lot in 6 months?
Why did you stop with the nopox? It takes a while to work, but it does well as a nitrate reducer. (as does all forms of carbon dosing - vodka, vinegar, nopox, biopellets)

 

[AbsoluteZer0273]

Thanks tripdad, I have a brightwell plate in the sump. I added it after the dsb and bioballs were removed. Another lfs suggestion. Would that be equivalent to the siporax?

 

[Reefing Madness]

http://reefkeeping.com/issues/2008-08/nftt/index.php
https://www.reef2reef.com/threads/whos-still-vodka-dosing-and-hows-it-going.82101/

 

[FugeTown]

Dr Tim paging Dr Tim's waste away please report to the high nitrate tank immediately.

 

[AbsoluteZer0273]

Thanks spiraling. I use an api test kit for phosphate. I have written down the phosphate as less than .25ppm lately because I don’t think it quite matches the 0ppm color on the chart. Which I know is imprecise, but always wrote it off as a good thing to have very low phosphate. As I have interpreted phosphate to be one of the worst things in a reef tank from my Lehman’s knowledge of the chemistry at work here.

 

[AbsoluteZer0273]

I stopped nopox after a few months because I saw no change in the nitrate level, but my ammonia started to rise. Since stopping the nopox my ammonia is back to zero. I was told nopox was a good way to help my tank while my biopellet got seasoned.

 

[nautical_nathaniel]

I'm not sure why they would recommend you remove the sand bed, that would have held a ton of beneficial bacteria for your cycle. Not saying add it back now, but maybe slow down on the changes and see how something works for a couple of weeks at a time before trying something else. For now I would add some Dr. Tims or something similar as FugeTown suggested and see what happens for a week. It's gonna take time and patience for anything to work if you give it the chance. It's hard, I know, but you will have a better reef tank because of it, not that your reeftank is bad now, it just needs a little adjustment here and there to get those nitrates down.

 

[Nart]

Just chiming in here about the Phosphate.
Since you do know that API's Phosphate test kit is for high-range.. Phosphates around 0.25PPM is actually still really high. I usually aim for 0.02PPM or less.

 

[tripdad]

Thanks tripdad, I have a brightwell plate in the sump. I added it after the dsb and bioballs were removed. Another lfs suggestion. Would that be equivalent to the siporax?

It is sold as similar, but after looking at all the available products and asking around i have found the Siporax had the best reputation for working. It is VERY porous, you can actually breaathe thru it.

 

[Ashish Patel]

Your nitrates are this high even with using pellets and NOPOX is puzzling to me. Could be something much deeper in your system. Inadequate biological filter and nutrient export, Sandbed issues, flow issues.
I am struggling to bring my nitrates up past 0.2 and figured I am fine with this number since colors are ok. Send pictures of your tank and sump so we can better help. Don't pay attention to redfield ratio once you get your tank back on track and stop using NOPOX and pellets the redfield ratio will work itself out. Using pellets and such will cause PO/NO balance.

 

[mcarroll]

So the tank is not quite a year old and showing nutrient buildup.

This tells me you may have rushed adding your livestock and therefore have overwhelmed your tanks bio-filtration potential. The buildup of ammonia when you tried to "dose away the nutrients" indicates this as well.

Did you start with dead rock?

I have a biopellet realtor with a little over a liter of pellets in it with a slow tumble, running for 6 months, and drains directly into my protein skimmer.

Thanks tripdad, I have a brightwell plate in the sump. I added it after the dsb and bioballs were removed. Another lfs suggestion. Would that be equivalent to the siporax?

I use an api test kit for phosphate. I have written down the phosphate as less than .25ppm lately because I don’t think it quite matches the 0ppm color on the chart.

always wrote it off as a good thing to have very low phosphate. As I have interpreted phosphate to be one of the worst things in a reef tank

You're not alone in thinking that way about phosphates, but it's not correct. N and P are two of the most critical nutrients for growth, repair and reproduction of every organism in your tank.

You're also not alone in thinking once you've added "too many nutrients" that you can just take them back out with a filter of some kind. However, that's also not correct. Ecosystems just don't work that way.

I would remove all the extra plates and filters and any other extra nutrient removers and get back to the basics: Live Rock. Skimming. Lights. Snails.

I would also get a better read on your PO4 level – I would acquire a Hanna meter, or take a sample to your LFS to be tested if they use one. I would not yet assume you need to add anything (but you might). Once you take all the extra competition for nutrients offline things may change on their own. Plus the test results might be different from a more accurate test. If you really are running at/close to zero on PO4 that's very very bad.

 

[AbsoluteZer0273]

I started with reef saver rock. I didn’t cycle it first, only rinsed it with ro/di water. Because it was mined from the middle of the state and didn’t have dead sponges and other dead organisms on it I figured it would cycle with the rest of the system. I used 230lbs! And 180lbs of live sand. I also had 60 lbs of sand in my refugium. Which has since been removed. When I “re-scaped” the display I put the excess rock in the sump.

 

[AbsoluteZer0273]

This is the original setup.

 

[AbsoluteZer0273]

This is a more resent picture.

 

[mcarroll]

I started with reef saver rock.

Is this a type of dead dry rock, or was it being kept "live" at the store in a rock tub?

I think your microbial community is simply under-developed from being small and limited in diversity to begin with AND starved.

What do you have for flow in the tank? (hard to see in the pics)