Nitrate problem driving me up a wall...

BRS
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We could kick around a host of ideas about how to lower nitrates - larger refugium, different set-up on your algae scrubber, etc, etc - or we can jump to something likely to get your nitrates down to safe parameters in a reasonable amount of time. There are lots of reasons why your nitrates could remain at 20 ppm (high by reef standards, unsustainable by SPS standards). Your best bet for real results, within a time period that's feasible is a sulphur nitrate reactor. I've personally used the Korallin Zucht bio-denitrator for a number of years with good success. The only media that needs updated is the calcium media as it dissolves, preventing ph drops. Easy to set-up and use, and offers good results, often bringing nitrates of 20 down to 0-3 ppm.
 
By the way I've tried about every method of lowering nitrates - bio-pellets, soluble carbon, zeovit, etc, etc. Sulphur nitrate reactors are the only devices I've seen work within a reasonable amount of time, again and again.
 
WWC
If it were me I would just do a 100% water change every 2 weeks cant go wrong with that. Otherwise I would jsut add some chaeto to the tank if I didnt want to change my water but once or twice a year.
 
rock_lobster said:
If it were me I would just do a 100% water change every 2 weeks cant go wrong with that. Otherwise I would jsut add some chaeto to the tank if I didnt want to change my water but once or twice a year.
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Two issues with these approaches. One, 100% water changes aren't really applicable to reef tanks. They aren't uncommon in freshwater Discus breeding and when used in this application, often 100% water changes are done daily. 100% water changes are so detrimental to the bio-filter within a tank, that to utilize them, the aquarist must understand that the bio-filter is severely weakened and cannot be relied on 100% to complete the ammonia cycle. In reef tanks, bacteria exists in live rock, the sand bed, the refuge, etc, etc so there is a good chance the bio-filter would replenish to occupy the water column (since most of your bacterial filter in on media and rocks anyway). Still, there is bacteria within the water column to some extent and you risk a massive change of water chemistry with a 100% water change. I wouldn't suggest it, at anytime on a reef aquarium. 10% water changes daily are an option when looking to reduce nitrates via water changes.

Cheato macro-algae does assimilate nutrients, but its function is limited. In a tank with such high nitrate, it's unlikely that cheato alone would be effective, unless used in something like a Pax Bellum reactor or intense up flow algae scrubber. Here, cheato could be removed quickly as it grows and the environment would encourage consistent growth at all times.

Personally, I've found that microbes are more effective in lowering nutrients (phosphate/nitrate) than macro-algae. Bacteria just seem more efficient and easier to cultivate, IMHO. This is the basic principle behind sulfur based nitrate reactors, which use sulfur as a media to encourage a bacterial cycle, with the bi-product of assimilating nitrate. Within 30 days, most sulfur based nitrate reactors are cycled and dramatically reduce nitrates, often down to 0 ppm. They are essentially maintenance free, aside from adjusting the output level (often 1-5 drips per second) and replacing calcium media (which is often only done once or twice per year).
 
Prodibio & combination of mb7 work great.

I run no reactors, but for carbon & skimmer, & no other nutrient removal aides.
Feed very generously and keep physical maintenance up to par.

Keeps no3 & po4 stable, just need to find the sweet spot of addition vs. Time vs. Feeding habits as the direction are to often for me.
 
Avast
gosnell gives some good advice. Sulphur based denitratification is an old and proven technique which has many advantages over chaeto, ats, or carbon based approaches...and while it generally not well know, it can also sequester significant phosphate as well as iron.

Its easy, cheap reliable, space efficient and extremely effective. And best of all its "out of column", meaning there is next to no chance of crashing your system should power, skimmer or circulation fail.

here is a video that shows its simplicity and setup...
I've posted a DIY version here on reef2reef that I run on my 400g system. I use very little rock and it keeps up easily with a high fish/coral load with heavy feeding.
 
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That video features good ol' Bill Wann, not only an aquarium genius (and genius in many other regards) but owner of the countries' largest private marine aquarium. I am not sure why sulphur based de-nitrification isn't used more, and because it was developed by a professional aquarist at a public aquarium, it under-went significant scrutiny and testing when it was developed. I think many aquarists hear sulfur mentioned in a filtration context and think bad news, but as @robert pointed out, it's an out of column filtration method which is HIGHLY unlikely to cause any serious system issues. One thing I've personally found, is that the slow flow rate of sulfur reactors causes issues where the pumps stop moving water through the reactor. If left un-attended, this problem could allow the reactor to de-cycle. The best fix is to ensure the reactor's (or pump's I should say) feed tube is located high enough from the reactor to allow for a natural siphon. I have my reactor's feed tube disguised in my overflow, where a natural siphon is created running down to the pump and the pump moves water through the reactor, producing a slow drip as affluent.
 
@chefjpaul - for some systems the use of soluble carbon alone works well. Soluble carbon (vodka and a host of additives) leads to anaerobic bacteria blooms, which in some cases can strengthen anaerobic bacteria already existing in the system. However, in many cases there isn't enough anaerobic bacteria within live rock because our reef tanks require so much flow and thus so much aeration. Often refugiums are under-sized for the tank and depending on their set-up, don't have enough anaerobic bacteria either. In these cases, soluble carbon simply incites blooms that temporarely assimilate nitrates, then die off. Bio-pellet reactors attempt to colonize anaerobic bacteria into a reactor made up of soluble carbon balls, which in some cases can lead to cyanobacteria outbreaks because the bacterial population is so high and volatile. Sulfur reactors create a chemical reaction, in which nitrate is assimilated and are IMHO more effective and come with less side effects.
 
Avast
Top Shelf Aquatics
jeremy.gosnell said:
@chefjpaul - for some systems the use of soluble carbon alone works well. Soluble carbon (vodka and a host of additives) leads to anaerobic bacteria blooms, which in some cases can strengthen anaerobic bacteria already existing in the system. However, in many cases there isn't enough anaerobic bacteria within live rock because our reef tanks require so much flow and thus so much aeration. Often refugiums are under-sized for the tank and depending on their set-up, don't have enough anaerobic bacteria either. In these cases, soluble carbon simply incites blooms that temporarely assimilate nitrates, then die off. Bio-pellet reactors attempt to colonize anaerobic bacteria into a reactor made up of soluble carbon balls, which in some cases can lead to cyanobacteria outbreaks because the bacterial population is so high and volatile. Sulfur reactors create a chemical reaction, in which nitrate is assimilated and are IMHO more effective and come with less side effects.
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I was not in disagreement at all, just pointing out options, as there are many, all with some effects positive and negative.

Not everyone will, can, nor able to set up a sulfur reactor.

I should also have mentioned my sump volume is about the same as display currently with ample amount of live rock and an oversize skimmer.
 
chefjpaul said:
I was not in disagreement at all, just pointing out options, as there are many, all with some effects positive and negative.

Not everyone will, can, nor able to set up a sulfur reactor.

I should also have mentioned my sump volume is about the same as display currently with ample amount of live rock and an oversize skimmer.
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Sadly we see sumps or HOB refuges offered for sale, that have a refuge volume of about 3-5% of the entire system volume. My personal sump is an 80 gallon custom built sump, with a 20 gallon refuge for a tank (with sump) that tops 300 gallons. Less than 10% refuge space won't have the intended effect a refugium is to have. Since I use a microbial system to denitrify my aquarium, I wasn't overly concerned about refugium size. To get the full de-nitrification potency of a refugium, you really need it to be sized at least 25% your total system volume. The Triton system has done a good job of pointing this out for people following their methodology closely.

Further confusing aquarists is the use of algae scrubbers, algae reactors, etc, etc. One important thing to note about de-nitrification (and making the decision between macro-algae based systems and microbe based systems) is that it's best to pick a system and dedicate your effort toward that. For example, having a macro-algae reactor (like a Pax Bellum) and a sulphur based reactor is running a total contradiction. A refugium does tie into both microbes and macro-algae for denitrification, but it doesn't put particular emphasis on one or the other, and simply naturally uses both, much like a marine estuary.

I find microbes to be the most effective way of ridding tanks of nitrate, in cases where it remains unusually high. Macro algae reactors can be tricky to get going, and often require dosing micro-nutrients, which oddly enough adds more nutrients to a nutrient problem. I am not totally aware of how this works entirely, and am due a conversation about it with Pax Bellum's creator. We discussed it briefly, but I didn't get the nuts and bolts in detail.

Sulfur reactors are readily available and very easy to use. They can be installed on nearly any system, including those without a sump. They are perhaps one of the easiest systems to install and maintain, requiring a minor media top off every 6 months of so. The only concern they present is that the water leaving the reactor has a very diminished ph, but calcium reactor media is used to replenish carbonate as the water exits. Within a month, most sulfur reactors have reduced the nitrate content of water leaving the reactor to 0 ppm, and within a few weeks, the tank's nitrate value has fallen to under 5 ppm and within time will reach 0 ppm. Sometimes you get a bit of nitrate if you're feeding heavily, or the tank is heavily populated, simply because sulfur reactors create such a limited output (usually 3-5 drips per second) and cannot keep up with the speed of nitrate generation. The unit Bill Wann is selling that someone linked to above looks very nice, and the use of an ORP probe to determine how the unit is working is ingenious. I've not seen that on any commercial units, with the exception of his.
 
Why jump to the denitrification? Honestly, Why not just cut back on pellet feeding like recommended and see if it comes down? his phosphates are also high. I'd work on just feeding frozen for a bit and see what happens.
 
I changed the fitting and added what twilliard said to add. I will test nitrate and phosphate tommaro. My scrubber is working I believe I can clean it and it turns brownish black in a few day like I need to clean it twice a week. Has some green on it. Is the scrubber working then?
d4277897f9e8620bb62f5d2092f3a45b.jpg
 
Tidal Gardens
When it is really working, you'll have a thick mat of green algae on it. This image is heading the right direction, but it's not working hard yet. Maybe more light is needed.
 
BRS

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