What to do about sustained phosphate and nitrate problems?

[Sharkey18]

I need help. I am beyond frustrated. 

 

I have been battling VERY high nitrate and phosphate levels for about 6 months. I have lost ALL my sps. 

 

Nitrates are sustained between 10 and 20.

 

Phosphates are go between .4 and .15. Never lower than that. Lately they have been close to the .2 - .15 range, but still impossibly high. 

 

I was running GFO but the phosphate levels are too high for GFO to handle at a reasonable cost. I have been dosing Lanthanum chloride which is why I am getting it under .2, but it's a laborious system and not get getting the job done either. 

 

Total system volume is about 400g. Tank has been running for 1 year.  I am doing a 100g water change every two weeks. I started with dry Marco rock. I have heard that could be a source of phosphate leaching.

 

I am running 4 MP40's for flow. 

 

I have switched foods, feed VERY little these days, and even sold my large regal tang in an effort to reduce biomass. I would say that my tank is moderately stocked in terms of fish. Certainly not a heavy bioload. 

 

LPS, nem, and zoas are doing well. 

 

Yesterday, out of desperation I removed about 25 lbs. of live rock. I am concerned that the rock work was too dense and did not permit enough flow to remove detritus. The rock work is much more open now and I am working on blowing off the rock to remove as much captured detritus as possible. 

 

The rock I removed is in a 50g barrel in 1.025 salt water with a pump. I have not added a heater yet. No light. There were almost no live coral on the rock.  I am going to change the water in the barrel every week to see if the rock itself is leaching phosphate or nitrate. I assume there will be a small amour of die off, but eventually the barrel water  should get down to 0 nitrate and phosphate right? 

 

At this point I am going to just keep lps and zoas but would love to work toward better water quality to eventually have the sps tank that I want. 

 

Suggestions? 

 

Laura

[gmerek2]

I had a nitrate problem. Added a large refugium with strong 3watt LEDs make the chaeto grow and have to trim often. It took some time but worked great in the long run.

[ridetheducati]

Have you read the numerous threads on WAMAS regarding carbon dosing?

 

I hate to say it, but it cost to be the boss.  In order to maintain high water quality on 400g of water requires capital.  Short term, 4-5 cups of HC GFO changed monthly will lower phosphates, guaranteed.  I strongly recommend upgrading the skimmer, G4 is not adequate.

[Sharkey18]

Awesome, thanks!

 

I was also thinking of upgrading the skimmer. Was waiting for a larger AVAST but think I am going to need to upgrade sooner.

 

Also will upgrade the lights on the fugue. Right now I am only growing caulerpa, and not even very well… 

[monkiboy]

i agree with tony, that skimmer isn't doing any favors on a moderately stocked 400g volume.

 

what lights are you running over your refugium? is your refugium still only 20g? for nutrient export via macro cultivation to really be of benefit on a 400g volume system you really need to look to enlarge your refugium. you have the additional tanks that i think i one point you said you were going to use for bangai fry or the like. use those for additional 'fuges at this point.

 

also, upgrading the lights if they are not sufficient is a great idea. a lot of folks rely solely on a homedepot CFL curly bulb and while it gets the job done, it's nothing like a dedicated wavelength specific fixture or combination of PAR38s can provide. you want LOTS of the right kind of light over a fuge. i have a couple fuge-specific designed evergrow fixtures (similar to the one alan has over his fuge tank and having incredible growth) that you can try out for free if you want to see if it makes a worthwhile purchase down the road.

 

and just to make sure, your RO/DI is tip top and producing 0 TDS water for those 25% water changes you are doing every week? you running filter socks and changing out diligently?

 

i know we can get you back on track, laura. great job with the continued effort - chin up.

Edited November 24, 2013 by monkiboy

[TheyCallMeMr.703]

I'd take him on on the Offer for the light...
  And Upgrade Fuge, That would be your Best LongTerm bet, and it'll help cut cost actually, because soon you can throw away that GFO, or store for a rainy day. lol
   Home-Depot grow lights would work even, and they are Not even $20.. and Will have nice fast Growth, But the D120, tuned for Plant Growth, is your Very Best Bet. lol. UPGRADE FUGE.lol,
  and Can't hurt to grow Diff' kinds of Algea, Got some Cheato here, If You'd like... but I know there are allot of closer members that could probably spare some.
  Last thing I think.lol. What lighting schedule are you running for the Fuge???     With your levels, I'd just leave them on for 20-On and 4-Off, or just leave them on all the time .lol. 

[Sharkey18]

Awesome ideas. 

 

Yes the fugue is only 20g and I have some cheap lights over it. I was growing a lot of nice macro, but it has all died back. I was experimenting with Vinegar dosing and ALL my algae died, even the coralline. The only thing that survived was some caulerpa and it is still there but not growing very well. I stopped vinegar dosing a few moths ago. I must have been doing something wrong. 

 

I do run the fuge lights 24/7. 

 

I would definitely like to try those evergrows...

[lutz123]

Having never run an sps system or one this big, take this with a grain of salt...

 

Wouldn't throwing a refugium at it be just taking care of symptoms? I would think that in an sps system you should be aiming to have the water so clean that macro would have a hard time growing. I think Sharkey is right that something more is going on. 25% water changes should have an impact, unless that source isn't pristine. What are, and have been, parameters? Water source?

 

I agree on the skimmer.

[gmerek2]

Good point Ducati. I also beefed up my skimmer same time I added the 29g refugium. I never thought I would see 0 nitrates. Good strong lighting over refugium is key. A lot of people say theirs is not growing because of low nutrient. There are a ton of cheap refugium lights on the market that have no penetration on a giant chaeto ball. The refugium also allowed me to add more live rock and maybe later DSB. How the heck does it grow so fast with low nutrient? I have to throw away a basketball sized piece each week.

[zygote2k]

How about a simple Bio-pellet reactor? I've installed 4 in recent times and they drop nitrates down to non-existent while allowing you to feed tons of food. Counter the rising P04 from excess food with a fuge that is appropriately sized and you won't have to upgrade the skimmer. FWIW. growing plants 24/7 only works for so long as eventually they will crash and die from lack of darkness. This has been proven in the indoor growing industry.

[miggs76]

Look into Red Sea nopo4x....it's a modified form of carbon dosing and people have had great results.

[davelin315]

Laura, first I would figure out what the limiting factor is in terms of your macro algae growth.  I have had high nitrates ever since a tank crash that occurred after a toilet flooded and ran for hours unchecked on the floor above my tank (this is when I lost my sps).  My nitrates are still much higher than yours are and the question for me has been what is causing this issue - I've attempted controls such as a remote deep sand bed (44 gallon rubbermaid with high flow filled with sand), biopellet reactor, GFO, Carbon, Nitrate adsorption resins, sugar/vodka dosing, large refugium, you name it, but the nitrates don't go down and, to complicate things, nuisance algae doesn't even really grow all that well let along macroalgae.  I would say that something else is amiss that is limiting your tank's ability to export nutrients and the fact that you can't get a weed to grow like caulerpa raises concerns that there's something else going on.

[Coral Hind]

Do you feed nori? I was having the same issue as you and I switch frozen foods and also now limit my nori feedings. Since nori absorbs phosphates and nitrates to grow it makes since that once the fish waste would have high levels of both. I don't think replacing your G4 is going to fix the problem and it should handle the 250 display and breeders unless you have a very large fry population. Keep us posted on the rocks you removed and the levels of anything leaching out.  

[Sharkey18]

Wow, Dave, I feel your pain….I tested my nitrates today after a 100g water change and they were between 10 and 25…. ugh. 

 

The limiting factor in my fuge might be the light. They are not particularly good, and I leave them on 24/7. I might try turning them off during the day. 

 

I had a TON of macro algae growth until I started dosing vinegar. Then it ALL died ( except the caulerpa). I stopped dosing a few months ago but still do not get good growth. I recently added a second light which resulted in a cyan bloom so maybe the caulerpa will take off next. You would think with all these nutrients….

 

David: I do feed nori but only once a week, maybe twice.  I cut that back as well. 

 

One of the reasons I started pulling rock yesterday was most of it had no live coral on it and I am leaning toward taking everything apart and starting over….

[jaddc]

Wow, Dave, I feel your pain….I tested my nitrates today after a 100g water change and they were between 10 and 25…. ugh. 

 

The limiting factor in my fuge might be the light. They are not particularly good, and I leave them on 24/7. I might try turning them off during the day. 

 

I had a TON of macro algae growth until I started dosing vinegar. Then it ALL died ( except the caulerpa). I stopped dosing a few months ago but still do not get good growth. I recently added a second light which resulted in a cyan bloom so maybe the caulerpa will take off next. You would think with all these nutrients….

 

David: I do feed nori but only once a week, maybe twice.  I cut that back as well. 

 

One of the reasons I started pulling rock yesterday was most of it had no live coral on it and I am leaning toward taking everything apart and starting over….

 

 

Oh no Laura! Your tank is so beautiful and awesome -- I hope you get this problem fixed so you can enjoy it more.

 

Rob is right on the money about the lights. I don't have the experience of other reef keepers, but I am a scientist so I look at these problems from the molecule point of view. Here's my logic on how I would approach this if I had your tank.

 

1) Your system is huge. So water changes is a rough way to go. That means you need to export the nutrients.

2) Chemical export is expensive for your system size. It will also be a lot of work to keep exchanging the stuff. 

3) That means you need a biological export that fast growing to use up the phosphates and nitrates. 

 

So here's what I would consider as solutions.

 

1) Upgrade the refugium for more volume to grow more. The lighting is key and I would do some reading on hydroponics and indoor gardening. I would get the grow lamps that nurseries use for indoor growth and put it on the same timing that the pros use. You can use reef lights, but I think grow lamps are a bit cheaper. Of course, algae and plants are different but photosynthesis is a shared evolutionary trait. It has been known for a while that these machines are tuned for a light cycle called the circadian rhythm. If the lights are on 24/7 that rhythm becomes out of sync and causes death. Anything more than 16 hours is bad for this rhythm. I would shoot for 12 hours since that is the light cycle at the equator.  

 

In the larger fuge with awesome lighting, I would grow a variety of algae for diversity.

 

2) Biopellets. The easier version of dosing where the pellets serve as a food source for pelagic bacteria that use nutrients. A good skimmer then removes the bacteria.

 

3) Algae scrubber. Requires more equipment and labor to scrape off excess algae.

 

Here is how I see nutrients. It is not the excess but the imbalance that is the problem. (search for the redfield ratio as an example) The exact numbers of the nutrient ratio are the source of many nerd arguments at science conferences (and it is different for different organisms), but the premise is true. So if you pull out all phosphate and you still have a ton of nitrates, then you still have huge problem.

 

If the nitrate and phosphates come from biologics (feeding or death), then we need to export them using biological sinks (algae or bacteria). If the phosphate comes in from leaching, then chemical export is appropriate. If those two mechanisms get flipped, then the ratios get off and then there will still be issues in the long run. 

 

Hope that helps and good luck.

Edited November 25, 2013 by jaddc

[wade]

One thing I didn't really see was to test your source water.  Make sure it is very high quality - and make sure the salts you are using are good quality as well.  After that, check other inputs - are you feeding too heavily (can make low flow areas that capture detritus worse).  Directly feed your fish and leave the rest alone.

 

As an aside, many years ago, I used to charge $50/hr to help people do maintenance or set up reef tanks.  One guy kept insisting his water was fine, but his tank was PLUGGED with hair algae.  After 3 visits, I finally stripped the rocks, hand scubbed them, put them back and checked his freshly made water... his water had over 50ppm nitrates in it! He hadn't changed or checked his RO unit, even though he kept insisting he had.  I made over $500 on that venture... which could have been solved with new RO membrane and DI columns.

 

Other than checking inputs (the real problem) I'd look at your skimmer as others have recommended.  Skimming hard is key alongside feeding sparingly, especially to corals found on open reef (many lagoonal species are fine with high nutrients).

 

Good luck!

[Origami]

Laura, high nitrates and high phosphates may be pointing to over feeding or decay of some sort. Yes, dry Marco rock has been reportedly associated with phosphate leaching, but you're also experiencing elevated nitrates. That makes me wonder if you've got a biologic source that's freeing up both. Have you begun to test the water from the sequestered rock yet? Results?

[sachabballi reef]

well she had very high readings for 6+ months...wouldn't that have trapped the excess into her sand bed and rocks?  How long can it take to get it all released? It may not be what she is currently putting in (food etc) but what is stored?

[wade]

Once freely dissolved, the only way to trap N and P is to integrate it into proteins.  Generally, the algae will use up what it can very rapidly.  The problem is that then the excess protein (be it plant parts, bacteria, or otherwise) can stay settled in the tank.  Keeping it clean, pruning out algae, and controlling inputs should allow it to leave the system.  I'd even recommend using some lanthanum chloride early (for excess P) then going to a media based removal.  For nitrates, the only real source is sandbed, internal rock pore spaces, or export of proteins before they convert back into ammonia and start over.

 

25-30% water changes, heavy skimming (eg, wet), use of phosphate remover should do the trick in time... but it will take a while.

[YHSublime]

Laura is running a bare bottom tank, fwiw.

[wade]

Well, barebottom can certainly explain some of the lack of nitrate reduction, though certainly not all of it. The rock should be doing a share.  But, in reference to the "buildup" of N and P - It won't be around long if the source is taken care of quickly.

[mling]

I too have nitrate and Hair Algea issues.  I am thinking of getting the BRS dual reactor -> http://www.bulkreefsupply.com/brs-gfo-carbon-reactor-dual.html

Using BRS GFO and Biopellets in the "Carbon" side of the reactor.

Will this work i.e. GFO and Biopellets side by side ?

 

BRS suggest using 1 cup of Biopellets per 50 Gallons,  Since I have 200 gallons, would I have to by 2 dual reactors, and Laura with 400 would need 4 dual reactors ?

[davelin315]

I wouldn't do GFO if you're doing biopellets - the point of the biopellets is to cultivate bacteria to consume your nutrient load, running GFO will only strip the water of some of these nutrients and hinder the process of building up bacteria populations.

 

Laura, on a side note, I had a 125 when I lived in Chicago with a HUGE bioload but also tons of xenia in it which consumed the nitrates like mad.  Have you considered clams and xenia (that reminds me that I have to get my clams from Tom - poor guy has been caring for them for nearly a year!)?  Both consume large amounts of nitrates.

[ctenophore]

I wouldn't do GFO if you're doing biopellets - the point of the biopellets is to cultivate bacteria to consume your nutrient load, running GFO will only strip the water of some of these nutrients and hinder the process of building up bacteria populations.

 

Laura, on a side note, I had a 125 when I lived in Chicago with a HUGE bioload but also tons of xenia in it which consumed the nitrates like mad.  Have you considered clams and xenia (that reminds me that I have to get my clams from Tom - poor guy has been caring for them for nearly a year!)?  Both consume large amounts of nitrates.

I'd normally agree with you on the biopellets/GFO in theory, Dave.  But I've noticed that they don't really do much for phosphate compared to nitrate.  Even beyond the redfield ratio which should be roughly 16:1 nitrate:phosphate.  My experience is that they work wonders for nitrates, but a little GFO for phosphates is still needed.  But that's based on a sample size of 2 systems, so highly anecdotal.  If you have nitrates at 20ppm and phosphates under 1ppm, you'd think PO4 would be the limiting factor and nitrates wouldn't fall more than 16ppm.  But they will (IME), and phosphates won't change all that much.  Add a little GFO and you should get both down to very low levels.

 

Now the xenia filter I completely agree with.  I think with good lighting and flow, it is significantly more effective than macroalgae.  And it looks prettier.  I have significant xenia & soft coral populations in one place or another in every system I keep (except qt), and I feel it very much helps keep nutrients under control.  Sinularia also works as well as xenia IME.

[wade]

Just be warned... xenia are tank abusers.  Keep them contained to an area where you can exract and toss them later.  If you have a glass tank, scraping them off is pretty easy.  Once they are in your rocks... good luck.