Help!! Need ideas how to raise PO4

[nemeth27]

Hey everyone,

Here's an interesting one. Over the last year or two my tank has gone through a lot. It use to be a thriving sps tank an I was able to share many frags. Then I tried carbon dosing and the red cyno started. I tried everything under the sun to get rid of it. SB, biobak, coral snow, etc. etc.

Good thing is I got rid of almost all of it, bad thing is I put my tank in a bio bloom. Clear/white fuzzy things all over my rocks. I lot basically all of my sps corals STN from base up. So I decide to stop dosing anything, shutoff my gfo reactor and go back to doing basically just water changes.

After months finally the stuff on the rocks are gone and some coraline algae is coming back. The only algae/bacteria issue I have is bubble algae that is slowly getting better.

Everything looks good but nothing is growing. I've done to s of testing and I get the following below:
Sal: 1.025
Amm: 0
Nitrate:0
pH: ~8.1ish
Mag: 1350
CA: 420
Alk: 7-8
PO4:0.00000000

The corals in my tank are either not growing or slowly STN from base. So I figured that my PO4 is just too low. I even went to a local shop and had them check my water. They agree that it looks like my tank is too clean.

They told me to dose amino acids, using seachem "fuel". When I dose it the corals look better and my PO4 does go up, but in one day it goes back to 0.000 on my Hanna checker. I've now been dosing it everyday and even had my skimmer off for three days and its still back to 0.00.

I only have a very small amount a cyno, which you can't even see by 6pm at night (lights go on at 12pm). I also have some of the red cotton candy like algae that is mixed in with my cheato in my fuge.

Does anyone have any idea what is eating up all my PO4?

Sorry about the way too long post!

 

[Skynyrd Fish]

The algea in the fuge is eating it. Also how about adding some more fish food? You could start to feed a small amount of flake. Flake food has po4 in it. I could send you one of my po4 leaching rocks. LOL. I'd say back off on the gfo like you did, remove some of your carbon if your using it, and add one more feeding daily. wait 2 weeks and check your levels. Slow and moderate changes, and as you know it takes a couple weeks to see any results from changes made today.

 

[toothman]

I would think it is the residual carbon from carbon dosing too much for your system. Carbon dosing is very effective and I personally find it great for nitrate control. I would continue with your plan not carbon dosing for a while until things are back to normal. You really can keep a balanced tank with carbon dosing, just cut way back in the future, try adding only 1/5 of what you did in the past. Once sps are over dosed from carbon I have found they will stn from the base. It is hard to bring them back to normal health and feeding like they did in the past. One factor I would check, often over looked is your potassium may be low, buy a salifert k kit and add brightwell k if it is low. A reduction in k is always associated with carbon dosing especially if you used zeolites. Carbon dosing also generally stimuates cyano bacteria also.

As far a nutrients that is easy, the following will help: more fish, more food. I would be careful adding too much will make your cyano take off. Adding amino acids might actually bring down phosphates even more since most carbon dosing systems are limited by nitrate according to the Redfield ratio 16 nitrate to 1 phosphate adding aminos which in turn add nitrates, should stimulate more bacteria growth further reducing phosphate. This is why zeovit carbon source zeo start has nitrate in it.

Once a tank is out of balance it does take several months to recover, just be patient and go buy anther fish to enjoy. Just my more than 2 cents.

can you post a video or picture of your tank.

 

[nemeth27]

The cheato or the cotton link or both? Should I ditch both for now? I'm just worried about nitrates. Should I keep dosing the amino acids? Thanks for your advice!!

 

[nemeth27]

Toothman
Stopped carbon dosing almost 9 mths ago. Think I should still stop to amino acids? But I'll definitely try to additional feeding. How about using coral feast as well? Thanks again!!

 

[toothman]

Something really does not add up. If I stop carbon dosing in a week phosphate starts to rise. Look up the redfield ratio it is interesting, 106 carbons, 16 nitrate, 1 phosphate. Adding amino will lower your phosphate, if it is nitrate limited. The basic idea of carbon dosing is: you add carbon to add material for bacteria to use to grow, with out adding any more nitrate or phosphate. As the bacteria grow they pull out of your tank in the ratio of 106:16:1. If anyone of these factors is limited bacteria will not grow.

With out enough nitrate bacteria will not grow, aminos do turn to nitrate. If you still have residual carbon in your tank adding amino will continue to reduce phosphate. That is the only answer that makes sense.

I really do not like regular carbon in my reef tank. I also try to rely on carbon dosing to reduce phosphate and generally do not use gfo. I also think corals can become accustomed to gfo but they really do not like it. I have a huge fuge with chaeto and I think it really adds biodiversity, just looking at the chaeto you can see 25 pods climbing around.

It should not really matter what food you add they are not that different. Do stop the aminos.

 

[nemeth27]

I'll stop the aminos. I think I might

 

[nemeth27]

Take out the cheato for now too so it doesn't consume any PO4 either. Or is that asking for trouble?

 

[Skynyrd Fish]

Trim some of the cheato and if you have the red bushy stuff. Feed the corals and feed those fish. Small changes.

 

[toothman]

I would not take out chaeto, trim possibly. How do you measure salt, often times refractometers are not calibrated properly. Poor salt levels will make a system unable to recover properly. I am not totally convinced it is just low phosphate that is your problem. Do you have calibration fluid with 35 ppt, it is NOT best to use di water to calibrate to 0.0. Are you using good ro/di water. Do you feed your tank 2 times or more daily.

 

[nemeth27]

I use the 35ppt calibration fluid. I'm using ESV salt. The water coming out of my RO/DI unit is still at 0ppm. The one thing I've always done is not feed a lot. Even when I was carbon dosing, which I know is a big no no.

Since I stopped carbon dosing 9mths or so ago I've been feeding maybe 5 times/week. Which is why I think I've been starving my system all along.

I got rid of my chaeto which had the red bushy stuff in it. I'm going to pickup some tonight, but a less than what I had before. And I'm going to start feeding 2x/day. I guess I'll see how it goes.

Thanks!

 

[yano]

I use the 35ppt calibration fluid. I'm using ESV salt. The water coming out of my RO/DI unit is still at 0ppm. The one thing I've always done is not feed a lot. Even when I was carbon dosing, which I know is a big no no.

Since I stopped carbon dosing 9mths or so ago I've been feeding maybe 5 times/week. Which is why I think I've been starving my system all along.

I got rid of my chaeto which had the red bushy stuff in it. I'm going to pickup some tonight, but a less than what I had before. And I'm going to start feeding 2x/day. I guess I'll see how it goes.

Thanks!

Could be you are overskimming your system?

 

[toothman]

Salt sounds good, overskimming is a real thing as is underfeeding. You should adjust your skimmer so it skims dry. In the zeovit directions you should adjust your skimmer so it skims dry. I really think the benefit of carbon dosing is so you can feed more and still achieve low nutrients, not just achive low nutrients while feed the same or less. Would like to hear in the future how your tank is doing. I am going on vacation this week but if you need more chaeto in future, I can send you some with a bunch of pods in it n/c.

 

[nemeth27]

Thanks Toothman! I'll let you know how it goes. Have a great vacation!

 

[Ptyochromis]

You could add fertilizer to the tank lol. Phytoplankton cultures have a bit of PO4 in them from what is used to grow the phyto I would dose some, your corals will thank you.

 

[SantaMonica]

Remember that your P is really not zero... It's just below your test kit ability.

 

[nemeth27]

Thanks for the though. I did figure that. But what is happening to my corals is the same that happens ULNS systems when PO4 gets too low. And even though I'm now increasing feedings PO4 is not budging. That's why I asked for help.

 

[SantaMonica]

Since you dosed for a while, which pulled P from the rocks, and then you stopped dosing, P is going back into the rocks. This will make it appear that you don't have P, at least until the rocks fill up again in 12 to 24 months.

The red stuff in the chaeto sounded like cyano, which is it was probably meant low light.

 

[nemeth27]

Okay. I've been feeding fish(flake and mysis) and corals (coral feast and rods coral) twice a day and still going back to zero PO4. The corals still aren't encrusting and a couple receded a little but stopped.
I'm starting to get some cyno in the sand. Could the sand be clogged? It's about 3-4 inches thick.

I really don't know what to do anymore.

 

[SantaMonica]

Clogged with what?