I need serious help with my Phosphate issue SPS Dom

[Christopher Poore]

Hello All!

I have an SPS dominant tank. Over the past couple 3 weeks I've had serious Phosphate issues and a good amount of my SPS have been paling out, losing color, some sensitive one sticks have lost almost all polyp extension.

Roughly 4 weeks ago my Po4 was testing between .02-.00 using a Hanna Checker. A week after my .02 test I tested and it shot up .26. I stopped feeding twice a day and reduced my feeding from 2 PE mysis cubes a week down to 1. I also extremely reduced my Coral Feedings. I slightly increase the flow on my reactor that runs like 1/4 or 1/5 of the recommended amount carbon & GFO.
I continued to test over the next two 2 weeks. It slowly went down to .23-.20-.18-.16

Then it shot up to .23, then back down to .16-.13. I just did a 15% water change and it shot up to .26 again.

Once I'm back at the house I'm going to test my RODI; but my TDS reads .000 so I would be surprised if it was coming from there.

Any other places I should immediately start looking?
Should I increase the amount of GFO in my reactor? I dont want to pull phosphates too quickly and cause STN as I have a lot of higher end frags that are still new.

Thanks!

 

[Diesel]

How often you change out GFO?
Carbon does almost nothing to Po4.
What's your No3?
How's the skimmer performing.
I would back off on coral food overall, a good healthy diet on fish food will give you plenty of coral food due to fishpoop.
Your salt may contain a source of Po4.
You test your RODI at 0.0 TDS but after mixing a lot more happens, test your newly mixed water on Po4 and No3.

 

[Christopher Poore]

How often you change out GFO?
Carbon does almost nothing to Po4.
What's your No3?
How's the skimmer performing.
I would back off on coral food overall, a good healthy diet on fish food will give you plenty of coral food due to fishpoop.
Your salt may contain a source of Po4.
You test your RODI at 0.0 TDS but after mixing a lot more happens, test your newly mixed water on Po4 and No3.

My Salt? Really? It's a fresh batch of Fritz RPM.
Skimmer is doing well, recently vinegar cleaned for 3 days. I run it a tad wet.

I will test mixed salt and my RODI; thanks for the advice.

Could it possibly be from not removing excess chaeto?

 

[N4sty T4te]

Food for though and questions to ask:
A / If your testing your water after feeding with a Hanna checker that can throw off your PO4 test in a major way. Particles in the water cause major issues.
B/ Definitely Test your salt mix.
C/ Check the DI resin on your RODI, it goes bad pretty quick. I have to replace mine once every 2-3 months.

I'd prob use NOPOX for this particular issue. Easier to gauge the results and correct with frequent testing which I'm sure your already doing.

Also when is the last time you replaced any sand? Sand beds can be a PO4 trap.

Just a few thoughts man, best of luck!

 

[Randy Holmes-Farley Verified Community Expert]

I don't think it likely the phosphate is causing "pale" colors, but too low of nitrate might. Some SPS tanks do fine at 1 ppm phosphate.

 

[Christopher Poore]

Food for though and questions to ask:
A / If your testing your water after feeding with a Hanna checker that can throw off your PO4 test in a major way. Particles in the water cause major issues.
B/ Definitely Test your salt mix.
C/ Check the DI resin on your RODI, it goes bad pretty quick. I have to replace mine once every 2-3 months.

I'd prob use NOPOX for this particular issue. Easier to gauge the results and correct with frequent testing which I'm sure your already doing.

Also when is the last time you replaced any sand? Sand beds can be a PO4 trap.

Just a few thoughts man, best of luck!

Thank you for the response. I haven't replaced any sand since adding it. If I siphon some sand away will that raise my PO4?

 

[nautical_nathaniel]

What kind of rock do you have? I doubt it is the issue if your tank has been established for some time but some varieties are known to release PO4 like Pukani.

 

[Christopher Poore]

What kind of rock do you have? I doubt it is the issue if your tank has been established for some time but some varieties are known to release PO4 like Pukani.

It's live rock I got from a LFS about 2 years ago.

 

[Christopher Poore]

Food for though and questions to ask:
A / If your testing your water after feeding with a Hanna checker that can throw off your PO4 test in a major way. Particles in the water cause major issues.
B/ Definitely Test your salt mix.
C/ Check the DI resin on your RODI, it goes bad pretty quick. I have to replace mine once every 2-3 months.

I'd prob use NOPOX for this particular issue. Easier to gauge the results and correct with frequent testing which I'm sure your already doing.

Also when is the last time you replaced any sand? Sand beds can be a PO4 trap.

Just a few thoughts man, best of luck!

A- I test before I feed
B- I will, Thank you!!
C- I actually changed DI resin 3 weeks ago.

 

[N4sty T4te]

A- I test before I feed
B- I will, Thank you!!
C- I actually changed DI resin 3 weeks ago.

Sounds like you've got your bases covered, my next move would be to be more diligent with cutting back the chaeto and test the sand. Put a small amount in a container with fresh saltwater for a day or two and test to see if the sand is releasing. Deeper sand beds start to exhaust around 2 years or so if I'm not mistaken.

That's all I've got on it.

 

[Randy Holmes-Farley Verified Community Expert]

The main source of phosphate is nearly always foods, and there's no way around that.

Foods typically add 0.02 to 0.3 ppm phosphate DAILY:

http://www.advancedaquarist.com/2012/3/chemistry

If you want phosphate lower, focus on more export. But as I said, I doubt that is your main problem since SPS can look great at your phosphate levels or higher. Elevated nutrients usually browns corals, it doesn't "pale" them. Low nutrients, especially nitrate, leads to pale colors.

 

[Christopher Poore]

I've just tested a freshly mixed batch of Fritz RPM and I came up with .10 po4. Immediately afterwards I tested my RODI and came up with .14. How is this possible? I'm stumped and getting frustrated quickly. I'm trying carefully to not lose $2,000+ in coral.

I have a salifert test kit for Nitrates but I have difficulty reading the chart. I will test nitrates in a moment though. Assuming nitrates are low what are some safe/controllablea ways to increase?

 

[Randy Holmes-Farley Verified Community Expert]

I've just tested a freshly mixed batch of Fritz RPM and I came up with .10 po4. Immediately afterwards I tested my RODI and came up with .14. How is this possible? I'm stumped and getting frustrated quickly. I'm trying carefully to not lose $2,000+ in coral.

I have a salifert test kit for Nitrates but I have difficulty reading the chart. I will test nitrates in a moment though. Assuming nitrates are low what are some safe/controllablea ways to increase?

That isn't likely the main source, and I wouldn't agonize about it, whether it is accurate or not, unless it is not 0 ppm TDS water.

I discuss it here:

http://www.advancedaquarist.com/2012/3/chemistry

What about other sources of phosphate, like the "crappy" RO/DI water containing 0.05 ppm phosphate? A similar analysis will show it equally unimportant relative to foods.

Let's assume that the aquarist in question adds 1% of the total tank volume each day with RO/DI to replace evaporation. Simple math shows that the 0.05 ppm in the RO/DI becomes 0.0005 ppm added each day to the phosphate concentration in the aquarium. That dilution step is critical, taking a scary number like 0.05 ppm down to an almost meaningless 0.0005 ppm daily addition. Since that 0.0005 ppm is 40-600 times lower than the amount added each day in foods (Table 4), it does not seem worthy of the angst many aquarists put on such measurements. That said, tap water could have as much as 5 ppm phosphate, and that value could then become a dominating source of phosphate and would be quite problematic. Purifying tap water is important for this and many other reasons.