High NO3 and ZERO PO4 - how to proceed using NoPoX?

[rocknut]

So, I’m posting hoping to get some advice/education (maybe re-education) about how to move forward with my reef. Here is the quick nutshell version of where I am at: I have a 150 gallon display tank (about 160 gallons total water volume), that I rebooted about 18 months ago. Here are some of the details about my tank:

• I have 140 pounds of really good, aquacultured live rock in the tank from Tampa Bay Saltwater (rock is farmed in the Gulf of Mexico). 2-3” sand bed also from Tampa Bay Saltwater, with various cucumbers, urchins, and stars to keep this clean.
  
  
• 30” venturi skimmer from Lifereef. Really a great skimmer, switched from a Bubble King and haven’t looked back.
  
  
• ATI T5 Sunpower lighting
  
  
• (3) Apex WAV in tank pumps, with a Tunze wavebox
  
  
• Fairly low bioload: only have three fish in the 150 gallon tank, and feed one 1” square of homemade food each night.
  
  
• My water changes have gotten a little lax, honestly. I have always done a 15% water change every week, but this dropped to 15% once or twice a month. I’m sure this is the reason for my higher than normal NO3 level, but would figure that dosing NoPoX and having a lot of good live rock would keep this lower on its own? Maybe not?
  

I have always dealt with high NO3 levels (over the course of several different reef tanks), and that is what I am looking to address. The strange thing is that I have never had issues with PO4, only the NO3, which seems to be the exact opposite of what is typical? Right now I have NO3 levels of about 16 (maybe closer to 32 using the Nitrate Pro Test kit), but my PO4 is 0 (using a Hanna Phosphorus meter that measures in ppb). This seems to be legit, as I really have no nuisance algae in the tank at all, and only have to clean the glass once a week at most. My NoPoX dose has been between 2-3 ml/day total because the PO4 is so low.

I have been dosing Red Sea NoPoX for the past year, and have decided that I really want to push ahead with the whole system (NoPoX, Reef Energy A&B, Reef Colors, etc). Because I always seem to have such an imbalance between NO3 and PO4 I’m a little confused about how to proceed? I understand enough about the Redfield ratio to know that I need some PO4 in the water to be able to lower my NO3, so am a bit stuck. I figure my options are as follows: do some massive water changes to manually lower the NO3, and then maybe add some PO4 to the water using some Brightwell Aquatics NeoPhos to try to bring things back into balance?

Honestly, I would really like to figure out where my imbalance keeps coming from? I have always tended to run systems with a super low PO4 and high NO3, and have been a bit baffled by this. Would love to get some thoughts on this.

So, in summary: zero PO4, with NO3 between 16-32 according to the Red Sea Nitrate Pro kit. How to get this back into balance, and how to move forward with a NoPoX dose?

Thanks in advance, and please let me know if I forgot anything.

 

[Peng]

Seachem has phosphate additive you can rebalance. I would also add a few more fish and feed frozen food without washing them.

 

[BlueCursor]

I would raise the dosage of NoPoX to 5 ml/day. Once a week increase by another 2-3 ml/day until NO3 starts dropping. According to the NoPoX instructions, you should be dosing a lot more than you are. But I wouldn't jump up all at once. Take a few weeks so you don't shock everything.

I wouldn't worry about 0 PO4. There is probably plenty in the tank bound up with organic compounds. I would be more concerned about 0 NO3 and high PO4.

Keep the skimmer running. You don't say if you are skimming dry or wet. Skim wet until you get the NO3 much lower. This will help speed up the cleanup. I always skim wet unless I am on vacation. I remove about 1 cup of liquid a day from my skimmer. I have a 100 gal tank + sump + 20 gal refugium.

 

[rocknut]

I would raise the dosage of NoPoX to 5 ml/day. Once a week increase by another 2-3 ml/day until NO3 starts dropping. According to the NoPoX instructions, you should be dosing a lot more than you are. But I wouldn't jump up all at once. Take a few weeks so you don't shock everything.

I wouldn't worry about 0 PO4. There is probably plenty in the tank bound up with organic compounds. I would be more concerned about 0 NO3 and high PO4.

Keep the skimmer running. You don't say if you are skimming dry or wet. Skim wet until you get the NO3 much lower. This will help speed up the cleanup. I always skim wet unless I am on vacation. I remove about 1 cup of liquid a day from my skimmer. I have a 100 gal tank + sump + 20 gal refugium.

Thanks for the advice! Like I said, it is the zero PO4 that has been throwing me off, as the NoPoX instructions state to cut your dose in half if you get below something like 0.01 PO4, but that being said, cutting my dose down has not resulting in an increase in PO4 which is what I hoped for. I have always been concerned that a higher doseage without the PO4 levels will cause issues because the carbon source isn't being used without the necessary PO4 part of the equation? You are probably right about there being bound up organics in the tank, however, and I haven't really considered that.

I skim fairly dry at this point, and remove some really nice "mud" consistency skimmate, but since I have a waste container hooked up with an auto shut off, pushing this towards a wetter consistency is an easy adjustment. This is another thing that has been frustrating for me: no matter the size of my skimmer, it never seems to make a difference regarding my NO3 levels. I have read countless threads where it is stated that "NO3 sits at zero because I have a big skimmer, and lots of live rock", which has never been the case for me. I also vacuum my sump regularly, and have very little detritus.

Again, appreciate you taking the time to read and respond. Thanks again!

 

[rocknut]

Seachem has phosphate additive you can rebalance. I would also add a few more fish and feed frozen food without washing them.

Hello Peng, thanks for the reply. I do have a bottle of the Brightwell NeoPhos, which I believe is basically the same thing as the Seachem additive? I used this in the past and although I was able to bump up my PO4 to 0.03, I didn't see the big drop in NO3 that I expected, which was again, confusing because: PO4 source + existing NO3 in the tank + Carbon source = should equal a reduction in NO3?
You are most likely correct about me needing to add some more fish, to bump up the PO4, but on the flip side, I would think that having a very low bioload would at the very least keep my NO3 lower since I do have a fairly large skimmer, lots of good live rock for denitrification, and am not adding a ton of organics to the tank in the first place? I guess that is the other reason for posting to this thread: I have had a reef tank for quite a while, but wonder if I missed some basic "Reef Tank 101" concepts, and am not to proud to ask for some "re-education" if I have something wrong.

 

[Peng]

I could only speculate that there was an imbalance and due to the depletion of phosphate, nitrate therefore couldn't be lowered. I would suggest adding phosphate by dosing slowly. Maybe simplify your nutrient reduction system by pausing the use of NP reducing products and let the levels naturally rebounce a bit to a normal ratio. I assume you are not using anything specific for phosphate reduction at this point?

 

[rocknut]

I could only speculate that there was an imbalance and due to the depletion of phosphate, nitrate therefore couldn't be lowered. I would suggest adding phosphate by dosing slowly. Maybe simplify your nutrient reduction system by pausing the use of NP reducing products and let the levels naturally rebounce a bit to a normal ratio. I assume you are not using anything specific for phosphate reduction at this point?

Yes, that is correct: I am not using any sort of PO4 reduction material, only the NoPoX. Thanks.

 

[Peng]

You can try AZ-NO3 which only decreases your NO3 level however I'd use it along with PO4 addition or pause the use of NPX

 

[SPR1968]

I'm in a similar position in that phosphate is 0-0.03 and nitrates are around 12ppm. I'm assuming their will be some phosphate anyway due to feeding and testing error (Hanna).

I've being dosing NoPox for over a year and currently use around 16ml per day in my Max S 650 so assuming around 550litres of actual water. You should be dosing 3ml per 100 litres at your Nitrate levels. I've been up to 4ml per 100litres for a few days but some corals didn't like it so I backed off. (The higher dose was suggested by Red Sea after seeing Skim colour so not just my idea)

I have lots of fish and corals so a high bioload and I would like to feed the fish more (to stop my Regal Tang eating zoas!!) but I need to keep the Nitrate in check.

I use Rhowaphos for the phosphate as NoPox would not keep them in check and they crept up.

My current experiment for Nitrate is I've got a Brightwell XPort NO3 brick which I added last week and I've also added a bag of around 250g Purigen so will see what these do in a few weeks.

 

[Velcro]

I was in the same situation. I dosed phosphate while using NOPOX.

 

[rocknut]

I'm in a similar position in that phosphate is 0-0.03 and nitrates are around 12ppm. I'm assuming their will be some phosphate anyway due to feeding and testing error (Hanna).

I've being dosing NoPox for over a year and currently use around 16ml per day in my Max S 650 so assuming around 550litres of actual water. You should be dosing 3ml per 100 litres at your Nitrate levels. I've been up to 4ml per 100litres for a few days but some corals didn't like it so I backed off. (The higher dose was suggested by Red Sea after seeing Skim colour so not just my idea)

I have lots of fish and corals so a high bioload and I would like to feed the fish more (to stop my Regal Tang eating zoas!!) but I need to keep the Nitrate in check.

I use Rhowaphos for the phosphate as NoPox would not keep them in check and they crept up.

My current experiment for Nitrate is I've got a Brightwell XPort NO3 brick which I added last week and I've also added a bag of around 250g Purigen so will see what these do in a few weeks.

Thanks for bringing up my current dosing, and what it should be per the NoPoX instructions, because that is surely part of my issue: I know that with my high NO3 levels I should be doing 3ml/25 gallons (so +/- 18ml/day), but since my PO4 has zeroed out, that level would dictate a much lower doseage: if PO4 is less than 0.04, but higher than 0.02, then the dose should be 1ml/25 gallons. So again, that is catch 22...

At this point I have started doing 25% water changes (40 gallons). I did one on Saturday, another yesterday, and will do one tonight (Monday). I have also started dosing Brightwell NeoPhos, to try to add some PO4 to the water. Figure that if I can manually lower the NO3 with the water changes (trying to get it below 10), and manually add the PO4 with the supplement, hopefully I can get things back into balance where the NoPoX will have enough Carbon/Nitrate/Phosphate to start doing its job?

 

[rocknut]

I was in the same situation. I dosed phosphate while using NOPOX.

How long did it take before you noticed a reduction in NO3?

 

[Velcro]

How long did it take before you noticed a reduction in NO3?

Took a couple weeks to really start hitting them.

 

[rocknut]

Took a couple weeks to really start hitting them.

Awesome, thanks so much. Out of curiosity, do you remember which product you used? Curious about how large your tank is, and how much product you were using each day? Just asking because I am initially adding 2ml each day of Brightwell NeoPhos to my 150 gallon. So far, after three days, my Hanna Phosphorus is still reading ZERO.

 

[Velcro]

Awesome, thanks so much. Out of curiosity, do you remember which product you used? Curious about how large your tank is, and how much product you were using each day? Just asking because I am initially adding 2ml each day of Brightwell NeoPhos to my 150 gallon. So far, after three days, my Hanna Phosphorus is still reading ZERO.

I used aquavitro activate. I can't remember the amount to be honest. Just sorta titrated it up until I was at about 0.1ppm

 

[Scott.h]

Aside from numbers on a test kit, what's the need to change it?

 

[Pmj]

I agree with keeping up dosing phos. I had 30-50 nitrates for months and kept upping nopox, vinegar/vodka solution, aquaforest carbon dosing, and was running GFO. I ended up with a bad case of dinos, nearly undetectable phos via Hanna ULR, and still had nitrates. Lost a bunch of corals from both the dinos (sticks and a purple gorg) and the low phosphate (acans and euphilia shrivel and die).

I stopped all carbon dosing, had to do blackouts, but dosing phos 100% showed improvement quickly. I had to dose phos every other day for a bit (phos kept dropping) and I'm feeding more. My nitrates are lower as well. Still not zero but if some nutrients work for WWC & BC then I'm fine not doing ULNS. I've just decided to stop chasing nitrate numbers (though I still check weekly).

 

[rocknut]

I agree with keeping up dosing phos. I had 30-50 nitrates for months and kept upping nopox, vinegar/vodka solution, aquaforest carbon dosing, and was running GFO. I ended up with a bad case of dinos, nearly undetectable phos via Hanna ULR, and still had nitrates. Lost a bunch of corals from both the dinos (sticks and a purple gorg) and the low phosphate (acans and euphilia shrivel and die).

I stopped all carbon dosing, had to do blackouts, but dosing phos 100% showed improvement quickly. I had to dose phos every other day for a bit (phos kept dropping) and I'm feeding more. My nitrates are lower as well. Still not zero but if some nutrients work for WWC & BC then I'm fine not doing ULNS. I've just decided to stop chasing nitrate numbers (though I still check weekly).

Thanks for the response! I had a similar battle with Dinoflagelates about two years ago, but we don't speak of that anymore....(shiver). Funny thing: I actually discovered NoPoX when I was battling them, and that is what finally wiped them out.
Looks like the consensus is to move forward with the PO4 dosing. Thanks again.

 

[rocknut]

So here is a quick cautionary tale: I ordered a box of Reef Crystals last week to use for my large 25% water changes, and have gone through about 80 gallons of it. Testing my levels in the tank tonight, expecting that my ALK would have gone up a little for its normal 8.0 dkh, since RC is usually on the higher side. It had actually dropped from 150 ppm, down to 130 ppm (so just above 7 dkh), even though my salinity was still fine at 35. I had my next batch of salt water mixed up in buckets, and was ready to do my next water change tonight, tested the salinity to make sure it was 35 (I use a scale to add the exact amount of salt to 20 gallons of water), then tested the ALK with my Hanna Checker. It was 50 ppm (which is 2.8 dkh). Double checked with my Salifert test kit: same. Then tested Calcium which came out to 90 ppm...
So, I'm going to contact Instant Ocean about this, and have already ordered some Red Sea salt, but that really sucks. Also, this was using the individual 50 gallons mix of salt, not in the bucket when the buffers and calcium might have settled on the bottom. I am mixing using almost the whole bag to get my 40 gallons of salt water.
Anyway, that might explain why my corals have looked worse after the big water changes.

 

[rocknut]

Quick update for anyone interested: Amazon sent out a replacement box of Reef Crystals which I had by Thursday. Mixed up my first 40 gallon batch (for a 25% water change), tested the newly mixed salt water, and looks like this batch is fine: mixed to 35ppt, Alk was 8.5, and CA was 440.

Did three 40 gallon water changes over the past three days, and have been dosing NeoPhos for the past seven (4 ml/day). Checked today and my NO3 is just below 8 using the Red Sea kit. My PO4 is now up to 0.06 (overshot that a bit, trying for 0.03), and I am dosing 2ml per 25 gallons, per day of NoPoX (so 12ml/day total). Now that my PO4 and NO3 are more balanced, I'm hoping the NoPoX can start doing its work. I'll update again later with the progress, but I think that big water changes to get the NO3 closer to where I wanted to be will be helpful, then letting the NoPoX start cranking away.