High nitrates, zero phosphates

[IslandLifeReef]

I see from your picture that you are using the LR Hanna phosphate checker, not the ULR checker. That checker has an error of +/- 0.04 ppm, plus 4% of the the reading. So, your PO4 could be 0.04 or lower, but not really zero. A lot of the methods that you are looking at to reduce NO3 rely on PO4 as well. These methods include carbon dosing and algae scrubbers. You have to look at your nutrients as limiting factors, i.e., things will only grow as much as the least amount of nutrient will let them. Since carbon dosing and algae scrubbers rely on organisms to consume nitrate, the nitrate reduction is limited by the available phosphate.

Looking at the pictures of your tank, you have a large bio load in fish. The fresh, self made food that you are feeding them is probably low in PO4, yet when consumed and excreted, is cycled to nitrate. I would suggest lighter feedings if possible, or supplementing that food with another food that is higher in phosphates. Flake foods usually have higher PO4.

The problem with reducing your NO3 with water changes is that you will also be reducing the already low PO4 by the same percentage. What you really need to do is figure out why you have such a nutrient imbalance and fix that.

Your tank looks good, so I would say that you have PO4 in there, just not enough for the LR checker to read consistently. Your NO3 may not be as high as you think as well. As @Ohashimz has said, you don't need to do anything drastic, just take it slow.

 

[maksim serebro]

That tank looks pretty nice for having such high nitrates (not hating). Kind of makes me think the test kit is off, Some nitrates boost colors, but alot of nitrates brown corals and your coral have a nice pop to them.

You know, technically you are right. The only algae I have is bubble algae. Colors are good but I’m lacking polyp extension on many lps and all sps corals. That’s why I’m worried about nitrates

 

[1mbrews8]

going through the same thing so tagging along!

 

[IslandLifeReef]

You know, technically you are right. The only algae I have is bubble algae. Colors are good but I’m lacking polyp extension on many lps and all sps corals. That’s why I’m worried about nitrates

Polyp extension could be affected by that Coral Beauty nipping at them. It looks like he was caught red handed in one picture.

 

[BeejReef]

It looks like you're getting good advise. I'll share my experience, just because it's awfully similar to yours.
I also had nitrates steadily creep up from under 4 (red sea) to 60. This happened at about the same time that my tank seemed to run out of phosphate. I suspect the rocks finally stopped leaching. I had never dosed it, but it dropped from a steady .05 or so down to .00, repeated tests over the course of a few weeks.

The only real export I've been running is a chaeto refugium. When I ran a skimmer, my nitrate and phosphate would both run at or near 0. Long story short, I dosed phosphate and the Nitrates came down fast. Faster than I wanted really. Each night before the refugium came on, I would dose the tank to about .30 phosphate. I did that four or five times and my nitrates dropped from 60 to 6.

However, I just tested last night and my Nitrates have shot up again to at least 40 since I stopped dosing P and shortened my refugium photoperiod. I thought the tank had gotten off track and I was just restoring equilibrium. Now, I'm thinking that my "equilibrium" will require ongoing P dosing or some other method of N control.

 

[maksim serebro]

Polyp extension could be affected by that Coral Beauty nipping at them. It looks like he was caught red handed in one picture.

You know I tried to catch that dang fish to no avail. Don’t know if it was him. Possible. He is nipping at rocks all day long. I either have to take apart the tank or move coral to qt and see if polyps open up.

 

[maksim serebro]

The other thing I’m thinking is setting up a frag tank, moving my corals there until I’m able to stabilize the display tank. The frag tank would have one little fish just for nutrients and tons of live rock.

 

[maksim serebro]

It looks like you're getting good advise. I'll share my experience, just because it's awfully similar to yours.
I also had nitrates steadily creep up from under 4 (red sea) to 60. This happened at about the same time that my tank seemed to run out of phosphate. I suspect the rocks finally stopped leaching. I had never dosed it, but it dropped from a steady .05 or so down to .00, repeated tests over the course of a few weeks.

The only real export I've been running is a chaeto refugium. When I ran a skimmer, my nitrate and phosphate would both run at or near 0. Long story short, I dosed phosphate and the Nitrates came down fast. Faster than I wanted really. Each night before the refugium came on, I would dose the tank to about .30 phosphate. I did that four or five times and my nitrates dropped from 60 to 6.

However, I just tested last night and my Nitrates have shot up again to at least 40 since I stopped dosing P and shortened my refugium photoperiod. I thought the tank had gotten off track and I was just restoring equilibrium. Now, I'm thinking that my "equilibrium" will require ongoing P dosing or some other method of N control.

Seems like your experience is similar to mine. Did you see any effects on corals as nitrates rose and fell?

 

[looneywun7]

i have the same problem!

 

[BeejReef]

Seems like your experience is similar to mine. Did you see any effects on corals as nitrates rose and fell?

I don't have a good enough eye for corals yet to give you a good answer. Most of my corals are little more than frags. The zoas and a few softies seemed to really like the high N and P. The LPS were pretty indifferent, though they don't like 0 phosphate. I only have a couple tester sps frags. Didn't see much either way.

 

[maksim serebro]

Well the nyos nitrate kit is in and it shows 25 ppm. API kit still shows 80 ppm. Still no reduction in nitrates despite water changes and running an algae scrubber. Feeding fish twice a day.

 

[Rylan5d]

Well the nyos nitrate kit is in and it shows 25 ppm. API kit still shows 80 ppm. Still no reduction in nitrates despite water changes and running an algae scrubber. Feeding fish twice a day.

Any luck since?