Nitrates vs. Me

[Treefer32]

I continue my eternal battle with nitrates. . . My phosphates are routinely under .1 on a regular basis. Anywhere from .05 to .1.

My export mechanisms:
1. Algae turf scrubber

• Running lights 24 / 7
• Letting screen fill in 3dimensional algae growth
• Enough hair algae the size of a soccer ball after 10-12 days of growth

2. Large Bubble magus auto roller mat

• Fills in with brown stuff a roll lasts around 3-4 weeks.

3. Oversized Diablo Skimmer with DC pump at max

• Pulls out 8-16 oz of solid black crud every 7-10 days depending how wet I have it set

4. 25 micron Nu-Clear cannister filter (just added 1000 ml of purigen to the cannister filter)

• I thoroughly spray with garden sprayer every 3 weeks and let soak in bleach water 2-3 weeks while the other clean cartridge is on. Then soak in RODI and Prime to eliminate chlorine.

5. I just upped my vodka dosing from 27 ml to 33 ml starting today per day.


I have a 340 gallon display with 75 gallon sump, 160lbs of Oolite sand and 160-180 lbs of rock. 4 year old tank established now with around 26-28 fish (I lost count). 4-5 of the fish are easily 8-10" in size now. (everything from thick huge Caribbean Blue tang to my long Eel like Wrasse that picks up everything not nailed down... )

I probably have a couple fish that are too large for my tank. At the same time they're pretty and fat and healthy fish!

My PH is remaining stable at 8.1 at night and around 8.2 during the day. With increased vodka dosing my alk consumption is going through the roof. I haven't added any coral. What I have is growing rapidly. I've increased my alk dosing from 10 ml an hour to around 14 ml an hour. And it's still staying around 7.7 dkh. I've gotten new reagent to verify my alk tester is correct. And it came up with the exact same reading with new reagent vs. my two month old reagent. I used to maintain 9-10 dkh with the dosing levels I was at. I've increased alk dosing by 50% and still can't keep up.

So, I'm trying to understand what's going on? Calcium tests show 425 with my last test. I used to be over 500 (6 months ago), so calcium is being consumed more rapidly as well. Magnesium is remaining stable at 1500.

Salinity remaining stable at 1.025 - 1.026. I'm dosing magnesium chloride with magnesium sulfite to get the sulfites in the water. I'm dosing trace elements from Red Sea as well.

I've run this tank for 4 years and been in the industry for well over 20. I'm stumped now. I'm o.k. with my nitrates 20-30. I'm probably not o.k. with them climbing to 40-60ppm.

I've added 1000ml of purigen to my cannister filter to see if that helps the nitrates. I'll need to give that 2-3 weeks to populate with bacteria before I do anything else.

Do I continue to increase vodka dosing?

I'm looking at the Brightwell bio bricks. Do I get one of those and place in the sump under my ATS to see if that helps with nitrates? I don't want them to bottom out either. Just trying to think of a long term plan to manage vs. a short term solution. Purigen, though it can be recharged with a simple bleach soak is not a long term solution in my opinion. I don't want to run a reactor. More expensive equipment to have room and plumbing for. . . .

 

[Dburr1014]

Perhaps you may be phosphate limited?
More phosphate will decrease nitrate more until it falls where your comfortable.
I'm a newbe with all the chemistry but it's a bump for ya.

 

[Randy Holmes-Farley Verified Community Expert]

I've added 1000ml of purigen to my cannister filter to see if that helps the nitrates. I'll need to give that 2-3 weeks to populate with bacteria before I do anything else.

Not sure what you want that to do. Purigen as a substrate for bacteria?

 

[Randy Holmes-Farley Verified Community Expert]

I've run this tank for 4 years and been in the industry for well over 20. I'm stumped now. I'm o.k. with my nitrates 20-30. I'm probably not o.k. with them climbing to 40-60ppm.

What is the most recent value?

 

[MaxTremors]

I would run your skimmer more wet (especially with the carbon dosing, you want it to be pretty wet to pull out the bacteria that is consuming the nitrates), you should be pulling out at least 8oz a day in a tank that big. I would also recommend adding a refugium if you have room, it’s likely that the turf scrubber just can’t keep up with the nutrients being added. You could also add a more intense light to the algae scrubber to increase growth. The purigen will help a little, but IME it works more like activated carbon. You could also feed less. I don’t think you are phosphate limited, that can impact every form of nutrient export, but so long as you have at least 0.03ppm or so, I wouldn’t worry. All that said, if your tank is doing well, I wouldn’t worry too much about slightly elevated nitrates, if you can keep them stable at 20-30ppm and your corals look happy, I wouldn’t worry about it.

 

[Treefer32]

What is the most recent value?

Nitrates as of 2 hours ago was 32. Nothing alarming, but wanting them to be managed vs. continuously increasing.


When I did my last water change in mid January they were 22. So 10 ppm in 4 weeks dosing 25 ml of vodka. Do I continue upping Vodka and testing weekly until the nitrates stop increasing? or implement a spot for bacteria to grow better?

I have a slime covering my gyres and overflow boxes now. It's a thick white slime. I assume it's large clumps of bacteria. Trying to figure a long term solution to managing nitrates. I don't care if they're 15, 20, or 25, if I could keep them there vs. in another month they may be up to 40 or higher. I don't know at what point nitrates start killing corals, but, I suspect I'm probably 2 months from it and it'll take that long to determine if any solution was effective.

 

[mdb_talon]

To me the magical fix was when i started dosing live phyto. I slowly worked up to very large doses of phyto daily and my nitrates now is always a battle to stay above 0.

I have seen enough reports of similar results that i dont believe it was just a coincidence. I also have a large refugium i pull about 3g of cheato out of weekly, but i had that before i started phyto. Otherwise i just have a properly sized skimmer and sometimes use a sock. I feed VERY heavy

 

[LeftyReefer]

I would add some Matrix to the sump and run your skimmer wetter.

8 - 16 oz of skimmate in 7-10 days does not seem like much...

My skimmer produces that much in a single day on a much much smaller system.

 

[Treefer32]

To me the magical fix was when i started dosing live phyto. I slowly worked up to very large doses of phyto daily and my nitrates now is always a battle to stay above 0.

I have seen enough reports of similar results that i dont believe it was just a coincidence. I also have a large refugium i pull about 3g of cheato out of weekly, but i had that before i started phyto. Otherwise i just have a properly sized skimmer and sometimes use a sock. I feed VERY heavy

I tried some live phyto. I didn't notice a huge difference, but I only did a daily dosing for about a month. What brands do you use? Phyto becomes expensive when you're dosing 30-50 ml a day for 340 gallons of water.

 

[mdb_talon]

@Treefer32 I grow my own. I do about 8-12 ounces a day on a 250g system. And yes to do in high doses is definetely cost prohibitive on large systems unless culturing yourself(which if you have the space is very easy)

 

[BostonReefer300]

I have several bags of ceramic bioballs that I got from BRS that I keep in my sump. I noticed all sorts of benefits about a month after adding them. I like them a lot because they are very sturdy and don't fall apart like those marinepure blocks. I agree with people saying to increase the wet skimming. Also, that white/gray slime is very likely bacteria given that you upped your vodka dosing. If you're getting blooms like that, I'd actually dial-down your vodka (and drink it instead). Do you have much algae growth in your tank?

 

[homer1475]

I tried some live phyto. I didn't notice a huge difference, but I only did a daily dosing for about a month. What brands do you use? Phyto becomes expensive when you're dosing 30-50 ml a day for 340 gallons of water.

I dose way more then that to 85G total water volume, and it's not expensive either. Look up @Eldredge, his 8 species live phyto is second to none, and he ships every Tuesday.

EDIT:
I'm up to around 3ml/g to my system and get a delivery every other week. My tank, and your's will thank you for it.

 

[Siberwulf]

@Treefer32 I grow my own. I do about 8-12 ounces a day on a 250g system. And yes to do in high doses is definetely cost prohibitive on large systems unless culturing yourself(which if you have the space is very easy)

Hold up... are you saying that dosing phyto actually dropped your nitrates? How does that work? Isn't it just bioload you're putting into the system?

 

[Randy Holmes-Farley Verified Community Expert]

Hold up... are you saying that dosing phyto actually dropped your nitrates? How does that work? Isn't it just bioload you're putting into the system?

Photosynthetic organisms are a sink for N and P, not a source, at least until they die.

 

[Siberwulf]

Photosynthetic organisms are a sink for N and P, not a source, at least until they die.

So...I'm probably hurting myself in the NO3 fight by dosing 30ml daily in my 90g. Dosing NO3 too, but if I can ditch that..I'd be happy.

 

[fryman]

Photosynthetic organisms are a sink for N and P, not a source, at least until they die.

In theory that's true but in my experience live phyto doesn't survive long in an established reef tank and thus doesn't affect nitrates or phosphates very much.

There are benefits to dosing phyto and I think it's great but I'm skeptical about using it to control nitrate.

 

[homer1475]

I dose quite a bit, and do not notice any difference in nitrates or phosphates because of it.

 

[Randy Holmes-Farley Verified Community Expert]

In theory that's true but in my experience live phyto doesn't survive long in an established reef tank and thus doesn't affect nitrates or phosphates very much.

There are benefits to dosing phyto and I think it's great but I'm skeptical about using it to control nitrate.

That may very well be true. I'm not making a claim about phyto, just how it may work.

 

[Treefer32]

I have several bags of ceramic bioballs that I got from BRS that I keep in my sump. I noticed all sorts of benefits about a month after adding them. I like them a lot because they are very sturdy and don't fall apart like those marinepure blocks. I agree with people saying to increase the wet skimming. Also, that white/gray slime is very likely bacteria given that you upped your vodka dosing. If you're getting blooms like that, I'd actually dial-down your vodka (and drink it instead). Do you have much algae growth in your tank?

No algae growth other than in the Algae turf scrubber. Nothing in the display.

 

[BostonReefer300]

No algae growth other than in the Algae turf scrubber. Nothing in the display.

OK, then I probably wouldn't worry too much about nitrate. I like to keep mine in high single digits, but plenty of people keep theirs WAY higher than that. What are you testing NO3 with?