Need some advice for chronic nitrates and carbon dosing.

[Murraydar]

We all, including the owner of that tank, have speculated on the lack of algae in such tanks. I suspect the lack relates to some trace element such as iron limiting its growth. That is the case in some parts of the ocean as well.

The presence of adequate herbivores also keeps algae down, as Lasse notes, but wouldn't likely prevent it from coating the glass quickly if algae had everything it needed.

Interesting. I don't often read about iron or trace elements relating to algae growth. Ill stick with my original plan, maybe try the dirty method someday when I have more experience.

 

[Bouncingsoul39]

Salifert and api. Use them both just to make sure the readings are correct. Regents aren't expired.

Both Salifert and API test kits are notoriously inaccurate for Nitrate specifically. Try Red Sea or Nyos and you will probably get a lower number. Also make sure you are doing the test exactly as instructed making sure you get uniform drop sizes and measure water precisely.

 

[Lasse]

I run my current tank with PO4 concentrations between 0.01-0.15 ppm and NO3 levels around 0.5 – 10 ppm. Add some trace elements and grow a lot of Chaeto. Do not think I have any limited factor for algae growth in this tank – still no algae problem but I clean the windows every 3 – 5 days. However – a lot of different grazers.

My old tank had unknown NO3 level (but it was high) and I read phosphorus levels exceeding 1.45 ppm. In the end of its lifetime I dose trace elements – still – no visible algae growth at all.

Lot of grazers. In the end I probably overdose potassium – my fishes and grazers died. However – the corals were better than ever. When I lose my grazers – I got an algae problem and I closed down that aquarium and order my new, special designed aquarium

For me - it looks like you have false reading of NO3. check your NO2 - because low levels (really low) interact very much with your NO3 readings.

Do you have bare bottom or gravel? If you do not have any areas that have anaerobic conditions - you will probably not have your NO3 levels going down very much with help of organic carbon dosing

Today I test NO3 on a regular base and I add NO3 every day.

Sincerely Lasse

 

[Reef Monkie]

Perhaps you might find this thing from the DIY section interesting, it is basically a PVC media reactor that creates a anaerobic zone for bacteria and allows you to directly dose the carbon to the bacteria instead of just pouring it into your tank. People seem to be having success with that, and its a pretty cheap thing to try.

Poor man nutrients control - Donovan's Nitrate Destroyer

 

[Murraydar]

I run my current tank with PO4 concentrations between 0.01-0.15 ppm and NO3 levels around 0.5 – 10 ppm. Add some trace elements and grow a lot of Chaeto. Do not think I have any limited factor for algae growth in this tank – still no algae problem but I clean the windows every 3 – 5 days. However – a lot of different grazers.

My old tank had unknown NO3 level (but it was high) and I read phosphorus levels exceeding 1.45 ppm. In the end of its lifetime I dose trace elements – still – no visible algae growth at all.

Lot of grazers. In the end I probably overdose potassium – my fishes and grazers died. However – the corals were better than ever. When I lose my grazers – I got an algae problem and I closed down that aquarium and order my new, special designed aquarium

For me - it looks like you have false reading of NO3. check your NO2 - because low levels (really low) interact very much with your NO3 readings.

Do you have bare bottom or gravel? If you do not have any areas that have anaerobic conditions - you will probably not have your NO3 levels going down very much with help of organic carbon dosing

Today I test NO3 on a regular base and I add NO3 every day.

Sincerely Lasse

It's possible my no3 readings could be off. I'll look into the no2 and no3 relations. I'll also be looking into getting a different nitrate test kit to confirm results.

I have a graveled display. Not deep sand bed, probably 2-3 inches deep or so. Lots of live rock, shouldn't that be enough for Anaerobic bacteria?

 

[Murraydar]

Perhaps you might find this thing from the DIY section interesting, it is basically a PVC media reactor that creates a anaerobic zone for bacteria and allows you to directly dose the carbon to the bacteria instead of just pouring it into your tank. People seem to be having success with that, and its a pretty cheap thing to try.

Poor man nutrients control - Donovan's Nitrate Destroyer

Pretty cool. I've looked into this solution (without the carbon dosing.) Is it true that only Anaerobic bacteria will consume nitrates though?

 

[Lasse]

It depends on - if you clean your sand now and when and if your living rock is solid - i do not think so

Sincerely Lasse

 

[acro-ed]

My SPS tank stays around 25ppm nitrate and my acros look great. I do not carbon dose; I do run a chaeto reactor and a cryptic zone/sponges.

Don't chase numbers.... just see where the tank looks good. If you want to pull the nitrate down as a starting point I guess that's fine, but don't worry about 30ppm nitrate as a major issue.

 

[Murraydar]

My SPS tank stays around 25ppm nitrate and my acros look great. I do not carbon dose; I do run a chaeto reactor and a cryptic zone/sponges.

Don't chase numbers.... just see where the tank looks good. If you want to pull the nitrate down as a starting point I guess that's fine, but don't worry about 30ppm nitrate as a major issue.

Ideally, I would love to not have to carbon dose. There's definitely side effects I would like to avoid. I'm not opposed to trying without carbon dosing and just letting things be.

Can you tell me a bit more about your tank? What are your po4 levels and how do you control them? I've also read that high nutrient tanks may have different / higher lighting and alk+Calc levels. Any truth to this?

 

[ChrisOFL]

We all, including the owner of that tank, have speculated on the lack of algae in such tanks. I suspect the lack relates to some trace element such as iron limiting its growth. That is the case in some parts of the ocean as well.

The presence of adequate herbivores also keeps algae down, as Lasse notes, but wouldn't likely prevent it from coating the glass quickly if algae had everything it needed.

I think lack of iron is what keeps the algae down in my tank but would it also affect chaeto growth? My chaeto grows just fine and is a lush green but I've recently noticed that the only time I have hair algae growth of any kind is when I dose a bit of iron. It usually browns out after a month and then I can remove it without it growing back. I can also go months without cleaning my glass in this tank and have always found that strange.

 

[Murraydar]

I think lack of iron is what keeps the algae down in my tank but would it also affect chaeto growth? My chaeto grows just fine and is a lush green but I've recently noticed that the only time I have hair algae growth of any kind is when I dose a bit of iron. It usually browns out after a month and then I can remove it without it growing back. I can also go months without cleaning my glass in this tank and have always found that strange.

Now I'm curious if removing iron from the water can help with algae. Cuprisorb supposedly removes iron, maybe I'll try it someday for the hell of it.

 

[ChrisOFL]

Now I'm curious if removing iron from the water can help with algae. Cuprisorb supposedly removes iron, maybe I'll try it someday for the hell of it.

Well another factor in my tank is that my phosphates have always tested at 0.00 without any phosphate removers but like I said, my chaeto grows well and if anything, carbon dosing (at the proper level) has made SPS in my tank grow better. Just keep up your carbon dosing, I was dosing 30mL/day in my 75 before I switched to NO3-PO4x. I actually prefer the product over vinegar dosing because it seems to cause less cyano issues for me.

 

[acro-ed]

Ideally, I would love to not have to carbon dose. There's definitely side effects I would like to avoid. I'm not opposed to trying without carbon dosing and just letting things be.

Can you tell me a bit more about your tank? What are your po4 levels and how do you control them? I've also read that high nutrient tanks may have different / higher lighting and alk+Calc levels. Any truth to this?

My main tank is 150g SPS only. Primarily bare-bottom with a spinkling of sand on one side (I keep a tiny bit of sand for the wrasses). There is a ton of flow (MP40/60/gyre/L1 return) and an oversized skimmer (iTech 400 cone). My phosphate is usually detectable, but low, at 0.02. My alk stays right at 8.1 dkh and my calcium a tad high at 440ish (trying to let that creep back down a tiny bit). I don't regularly test Mag but it stays around 1350. I dose Ca and Alk with a doser and top off with kalkwasser. I have 2x radion pro, an LED bar with blue/UV, and 4x T5.

I do not run any GFO and I do not carbon dose. I have a fairly large chaeto reactor (about 2g), and one compartment in my sump that is packed full of rubble rock which is now full of yellow and pink sponge. I periodically run a bag of activated carbon.

I generally feed 4-5x per day (flake/LRS/eggs/mysis/etc). I have a light to moderate stock of fish (1 tang, 1 rabbit, 1 clown, 6 chromis, 2 damsels, 2 wrasses, 1 bangaii). I may still add a couple more fish, but nothing too crazy.

There are about 60 different acros in there and most are growing well. This tank was started from scratch about 20 months ago (I wanted an acro tank from scratch with no pests).

I do believe that higher nutrient tanks need more light and higher alk. I also believe that higher alk in a high light/lower nutrient tank will burn SPS. Getting too far over on one variable on this spectrum will yield pale corals, or brown corals, or burnt corals.

My old sps tank was absolutely filthy and had MH/VHO and a few Tunze streams. I kept the alk around 9.6 (which would certainly burn the corals in my current tank). I never really tested the nitrate or phosphate, but there was lots of detritus settled in various places and the water was tinged yellow when I would do water changes (which wasn't often). I feel that the growth was actually better, but my growth is still decent now and the color is better overall. It's all a trade off. Certain acros loved the filthy tank with the 400w MH, especially true stags. Not every coral will like every tank.

In my current tank I battled dinos in the beginning but beat them (nutrients were zeroed out when I first started the tank), and later dealt with bryopsis which was limiting my chaeto growth. Once I killed the bryopsis the chaeto growth exploded and now everything seems to be in balance and the algae is growing where I want it. The nitrates have remained fairly constant despite any of this, however.

Hopefully some of this helps...

Thanks,
Ed

 

[Murraydar]

It helps a lot, I appreciate it. Tempted to try without carbon dosing again and just letting my nitrates be. I'm like 90% certain at this point that whatever was killing my sps a year ago probably wasn't being caused by nitrates. Probably overdid my alk or something and caused rtn.

How do you contain your chaeto? My sump is only around 25 gallons. There's room in protein skimmer chamber the chaeto but it constantly gets sucked and caught into the impeller, despite my attempts to contain it in bags and stuff.

 

[alex.mccann99]

What are you feeding your fish?!?! I had a 60 gallon with a 25 gallon sump loaded heavy with fish, all LPS and softies. I dosed 100 proof vodka through a BRS Doser daily about 6ml per day. I feed twice a day a couple cubes of mysis and pellets. I think an important factor was I also had my sump refugium area filled with a couple big blocks of MarinePure and a Skimmer rated for a 200 gallon tank. I consistently ran close to 0 nitrates.

I'm not saying all this to brag, just saying that you shouldn't have to dose Carbon in those huge amounts to sustain the beneficial nitrate eating bacteria that will allow you to achieve lower nitrates. One thing I always did was made sure all of the food was either eaten or it was removed. Whether my fish, CUC or corals ate it, I never let it flow down the overflow. I changed my filter socks every 3 days (I currently run my tank sockless and I'm having great results). Over feeding.is huge mistake people make. Not saying it's your issue, but maybe it is?

 

[Murraydar]

What are you feeding your fish?!?! I had a 60 gallon with a 25 gallon sump loaded heavy with fish, all LPS and softies. I dosed 100 proof vodka through a BRS Doser daily about 6ml per day. I feed twice a day a couple cubes of mysis and pellets. I think an important factor was I also had my sump refugium area filled with a couple big blocks of MarinePure and a Skimmer rated for a 200 gallon tank. I consistently ran close to 0 nitrates.

I'm not saying all this to brag, just saying that you shouldn't have to dose Carbon in those huge amounts to sustain the beneficial nitrate eating bacteria that will allow you to achieve lower nitrates. One thing I always did was made sure all of the food was either eaten or it was removed. Whether my fish, CUC or corals ate it, I never let it flow down the overflow. I changed my filter socks every 3 days (I currently run my tank sockless and I'm having great results). Over feeding.is huge mistake people make. Not saying it's your issue, but maybe it is?

Nah I feed very sparingly. Cube a day, if that, bit of seaweed every other.

 

[Scott.h]

The only way I'd consider your numbers to be a problem is if I had a nuisance algae problem. Add macro and up the carbon dosing if you need the numbers lower.

 

[Rakie]

Yeah your numbers aren't a problem to most of us here, as we said. 30ppm nitrates is just fine, it does NOT impede coral growth, but low no3 does... po4 also does NOT impede growth.

So to put it more bluntly -- You're trying to solve a non-existent problem.

 

[Hans-Werner]

Tested it tonight. Po4 at. 02 on my hannah checker. No3 was around 30ppm, checked with salifert and api tests.

I've looked into the 'dirty' sps tanks, cool stuff. Im fairly confident at this point that my nitrates were not the actual cause of my sps deaths. However, I would still like to get them down to around 5ppm. Just a good baseline to start over with I guess.

I agree, nitrate may not be your problem but 0.02 ppm phosphate may be your problem. You have a very low phosphate concentration and there is an imbalance between phosphate and nitrate. Organic carbon dosing may worsen the problem by driving the phosphate concentration even further down. So I would go with aeras and start dosing phosphate before I would start organic carbon dosing. SPS need some phosphate! I recommend 0.03 to 0.1 ppm PO4.

 

[aeras1131]

@Randy Holmes-Farley I agree that we have all speculated on the cause of recession in coralline algae in tanks. I could argue with your hypotheses about the trace elements overall. I change 5g weekly in my 75g total water volume reef to replace trace elements. I was on this maintenance schedule before I started drip dosing aminos and after I started drip dosing aminos. My intuition is that our corals are outcompeting coralline algae for nutrients. Does Anaerobic bacteria remove the trace elements out of the tank as well as the PO4/NO3? I believe the process for my bioreactor is this anaerobic bacteria takes NO3 + PO4 + O2 = Algae which is skimmed out by the skimmer. Do you know if the reaction is more like this? NO3 + PO4 + Trace + O2 = Nutrient rich Algae which is skimmed out. I am skeptical that my coralline algae was being trace mineral growth limited in one week with a weekly 5% Water Change. Please let me know what you think.