Phosphates super high

Justin 420

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I'm not sure why my phosphates are super high. My tank is a 90 gallon corner tank. My soft corals, and my hammers are doing fine. My chalice corals are not doing good. My Hannah low range test kit errors out on the high side. I didn't measure before I did my last two water changes. I've done two twenty gallon water changes in the list two weeks. I use filter socks, I change every 3 days. Small refigium that doesn't seem to be growing much macro. Bubble magus skimmer, some carbon and purigen. I've been using bright well aquatic phosphate e to help lower but still reading too high to read on the tester. Could my rock or sanded be leaching it.. i have a deep sanded. 3 inches in most places. Or more. A few months ago. Probably 4 months ago. I moved my rock work around and took a chance and cleaned my sand. It was still pretty dirty when I was done. Everything seemed to do OK after. Amy help. Please
 
I'm not sure why my phosphates are super high. My tank is a 90 gallon corner tank. My soft corals, and my hammers are doing fine. My chalice corals are not doing good. My Hannah low range test kit errors out on the high side. I didn't measure before I did my last two water changes. I've done two twenty gallon water changes in the list two weeks. I use filter socks, I change every 3 days. Small refigium that doesn't seem to be growing much macro. Bubble magus skimmer, some carbon and purigen. I've been using bright well aquatic phosphate e to help lower but still reading too high to read on the tester. Could my rock or sanded be leaching it.. i have a deep sanded. 3 inches in most places. Or more. A few months ago. Probably 4 months ago. I moved my rock work around and took a chance and cleaned my sand. It was still pretty dirty when I was done. Everything seemed to do OK after. Amy help. Please
Sounds like you may have been consuming a lot of YouTube or something similar.

What is "super high"?

Like most, you would have been better served by the regular Hanna phosphate meter.

Since for now you're stuck with the one you have, the next time you test dilute your sample by 50% with RODI water. If you get a good reading this way (ie no error), double the number on the tester's readout and that's your tank's concentration (but with half the certainty of the original test). If it still errors out, dilute twice with 50% RODI water and multiply the result by x4 to get your tank's number (but with 1/4 the certainly).

The PO4 number also matters in context not just by itself....

Can you also post the rest of your water tests, including NO3, s.g. and temperature?

Excess filtration (eg socks, phosphat E, etc) is unlikely to be helping matters. I would discontinue all of this until things have normalized.

Most folks seem to agree that a sand bed is best kept to an inch or two.....or even bare-bottom. 3+ is likely to become a mess as you found.

This also indicates a few other potentials.....that you are broadcast feeding and/or wasting food in the tank, and that your flow may be inadequate to keep particles afloat long enough for them to be consumed.

Stop broadcast feeding, if you are.

During normal feedings, make sure you only add as much food as your fish can consume BEFORE any of it hits the rocks, sand bed or filtration.

Consider rearranging your flow pumps, changing their programming, or possibly even replacing them if they turn out to be inadequate.

Last, how old is this tank?
 
Its super high but no number?
What are the nitrate and phosphate levels? How much do you feed, how often do you feed what type of food do you feed?
Do you have algae? If no algae what makes you suspect the phosphate is bothering the chalice but not the other corals?
 
You're providing issues and maintenance schedules but no p04 readings..
Make sure you're doing the test correctly and give us the reading here.

Also.. i'd be very careful of the things you're doing atm, you dont want to bottom out your nutrients. That will open up a whole new can of worms.
 
OP said the Hanna ULR is maxed out so that is in excess of 0.9. I've only used GFO to lower PO4 but 1 cup in a reactor brings 275g volume down to a detectable level. I overfeed but I choose to feed based on my fish needs not test results as many do.
Previous test was a flashing 0.9
PXL_20261004_165655196.MP.jpg
 
@mcarroll gave solid advice on how to get a reading.

Rock and sand can hold phosphates and release them into the water column as the phosphates in the water drop, yes. But high phosphates aren't necessarily a problem unless your corals are struggling or losing color, chasing numbers can be as bad or worse for your tank than letting it ride. A steady number is better than a constantly shifting "perfect" number.

Like @exnisstech my Phosphates are usually pretty high so I occasionally add some Rowaphos just to keep them testable.

You can reduce feeding or get some foods that are phosphate free to help reduce the amount going into the tank, but if everything is happy and healthy, be careful changing too much.

I also think I remember reading that dosing nitrates/ammonia/ammonium if they're low/out of ratio can help lower the phosphates. @Randy Holmes-Farley
 
Sounds like you may have been consuming a lot of YouTube or something similar.

What is "super high"?

Like most, you would have been better served by the regular Hanna phosphate meter.

Since for now you're stuck with the one you have, the next time you test dilute your sample by 50% with RODI water. If you get a good reading this way (ie no error), double the number on the tester's readout and that's your tank's concentration (but with half the certainty of the original test). If it still errors out, dilute twice with 50% RODI water and multiply the result by x4 to get your tank's number (but with 1/4 the certainly).

The PO4 number also matters in context not just by itself....

Can you also post the rest of your water tests, including NO3, s.g. and temperature?

Excess filtration (eg socks, phosphat E, etc) is unlikely to be helping matters. I would discontinue all of this until things have normalized.

Most folks seem to agree that a sand bed is best kept to an inch or two.....or even bare-bottom. 3+ is likely to become a mess as you found.

This also indicates a few other potentials.....that you are broadcast feeding and/or wasting food in the tank, and that your flow may be inadequate to keep particles afloat long enough for them to be consumed.

Stop broadcast feeding, if you are.

During normal feedings, make sure you only add as much food as your fish can consume BEFORE any of it hits the rocks, sand bed or filtration.

Consider rearranging your flow pumps, changing their programming, or possibly even replacing them if they turn out to be inadequate.

Last, how old is this tank?
^This
 
Its super high but no number?
What are the nitrate and phosphate levels? How much do you feed, how often do you feed what type of food do you feed?
Do you have algae? If no algae what makes you suspect the phosphate is bothering the chalice but not the other corals?
^This too
 
Define super high? My display runs at .5 yes that’s high, not .05 and everything is fine but I’ve lost some color on a couple sticks. The rest are super bright. 🤷🏻‍♂️
 
Hello. I'm back with some numbers.
I still got a .9 blinking after dividing in half. I did not have time to check again. I will when i get home from work. Nitrates with a Salifert kit shows what appears to be close to 100ppm. Alkalinity is 9. That's what i try to maintain. Temperature is 77. SG 1.025, calcium 450. Mag 1370. I feed 1 cube of frozen brine in the morning. I never have rinsed it.... at night I feed me life spectrum a+. I'm sure I've fed a bit much at times but not very often. I have no algae in my display..
This on what to try next. Vinegar???
 
Hello. I'm back with some numbers.
I still got a .9 blinking after dividing in half. I did not have time to check again. I will when i get home from work. Nitrates with a Salifert kit shows what appears to be close to 100ppm. Alkalinity is 9. That's what i try to maintain. Temperature is 77. SG 1.025, calcium 450. Mag 1370. I feed 1 cube of frozen brine in the morning. I never have rinsed it.... at night I feed me life spectrum a+. I'm sure I've fed a bit much at times but not very often. I have no algae in my display..
This on what to try next. Vinegar???
Change nothing, IMO.

If you aren't getting pest algare, there's basically no reason to do anything but wait for corals to use up these nutrients in due time. The nutrients aren't hurting anything.

Do regular small water changes to facilitate things in general....10-20% per week, nothing crazy.

How old is the tank again?

How about coralline algae?
 
Didn't see the latest - yeah I would agree. Leave it be.

If everything checks out OK with measurements, my next step would be an ICP-MS to look for heavy metals/pollutants.

EDIT - as to the reason for the weird losses. Not necessarily as to the reason for the high nutrients. Also - do you dose any kind of phyto, specifically dead and concentrated?
 
Thanks for your input and advice. I've had the tank up for 9 years now. I did start vacuuming the sand bed about 7 months ago. I was advised by a local reefer that if i do that, only do a small section at a time. Like 6 in sq area. That's what i did until I really stirred up things when i changed my rock work around. That was about 4 months ago.
 
I have used benepets reef food once every couple weeks. Nothing consistent in feeding corals
 
Coraline algae doesn't seem to be growing. I assumed it was from high nutrients
 
I use filter socks, I change every 3 days. Small refigium that doesn't seem to be growing much macro. Bubble magus skimmer, some carbon and purigen. I've been using bright well aquatic phosphate e to help lower but still reading too high to read on the tester.
I would discontinue these extras, even the filter socks, until things stabilize and you see some coralline algae growing.

At the very least it is pointless to have macro algae competing with your display, but it could actually be causing these problems as counter as that may seem. Get it down to just the live rock and protein skimmer.

Clearly it's not a lack of N or P causing things not to grow.

But Leibig dosn't lie....something (ie a smaller macronutrient or a micronutrient like iron.) is limiting growth and thus limiting uptake of the major macro nutrients, thus the buildup of NO3 and PO4.

Regular water changes should help replenish things like K, Fe and I, but the effect will be minor....it may only make a difference after you get the tank out of the competition it's presently in with the refugium, etc.
 

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