Help with Phosphate

[Noobreefer84]

Hello reefers

I’m struggling with PO4 and I’m not sure what to do anymore.

Water on Jan 19
Alk 8.5
Cal 480
No3 6.4
PO4 0.7
Mag 1290
Salinity 1.026

Added phosphate-e enough to reduce by 0.3p tested PO4 on the 21st and it went up to 1.0

22nd I did a 20% water change, added clear max to my rear chamber and more phosphate-e to drop by 0.3ppm and tested later in the day. It was 0.4ppm

Did a full test again today (23rd)
Alk 9.1
Cal 480
No3 6.9
PO4 1.4
Mag 1350
Salinity 1.027

Mag increased cuz I dosed to boost it to 1350 and nitrate bumped as I dosed after the water change to maintain about 6ppm or so.

I just can’t get my PO4 down and hold it.

Tank was set up in Oct, has 4 fish, 2 shrimp and a mix of frags. It’s an AIO with no room for a reactor.

Note that I have a RO filter and I tested. It comes out with 0.8 PO4. I know that’s an issue so I ordered 4 stage RODI which will be here end of next week.

I only feed once a day, mix of frozen brine and mysis.

I also swapped all my fine Fiji pink sand for Carib sea aragalive special grade on Boxing Day. My sand was blowing everywhere and I hated it

Any suggestions would be helpful. I’m at a loss

 

[KrisReef]

The best way to reduce p is to precipitate it out with lanthanum chloride. Since it's coming through the RODI (Which is another problem), just add LC to the RODI mix and then filter that through a 5 micron sock or just carefully decant the surface water and discard the settled precipitate and a little of the RODI slop water.

Of course, with the DI resin it should grab the P and solve the problem, but until then LC is quick for RO water treatment.

In the tank, you could also use LC. I have done it often and not had issues but some folks are careful and add LC dropwise into a sock in the tank to catch and remove the precipitate. Problem with P is that it binds to rocks and sand and then comes off when you lower the amount in the water column, making the process tedious to get the substrates "clean." Go slow, be careful, and get that DI resin in line to solve the issue.

Are you on a private well, or municipal water system?

 

[Noobreefer84]

The best way to reduce p is to precipitate it out with lanthanum chloride. Since it's coming through the RODI (Which is another problem), just add LC to the RODI mix and then filter that through a 5 micron sock or just carefully decant the surface water and discard the settled precipitate and a little of the RODI slop water.

Of course, with the DI resin it should grab the P and solve the problem, but until then LC is quick for RO water treatment.

In the tank, you could also use LC. I have done it often and not had issues but some folks are careful and add LC dropwise into a sock in the tank to catch and remove the precipitate. Problem with P is that it binds to rocks and sand and then comes off when you lower the amount in the water column, making the process tedious to get the substrates "clean." Go slow, be careful, and get that DI resin in line to solve the issue.

Are you on a private well, or municipal water system

Thanks.

A new membrane for my RO comes Sunday. Which hasn’t been changed in probably a few years. We just use it for drinking water before I got back into the Hobby.

RODI 4 stage comes next Thursday.

Ill just add a 2nd pack of clear max into the chamber for now and use Phosphate-e daily for the next few weeks or so to keep pulling it off the rocks and “clean” the rocks/substrate as you mentioned slowly. Thankfully my tank is small enough that 10ml = 1ppm reduction. I have a 500ml bottle.

Probably had this problem since Oct but it’s just consistently built up over time as my ATO has PO4 in it too

 

[Noobreefer84]

May I ask for someone to tell me if my "thought process" is on the right track with the below.

I was dosing Phosphate-e "heavily" for a week or so b/c my Hannah was testing 1.3 - 1.4 consistently.

I then decided "this doesnt make sense" so I bought a Salifert PO4 tester to double check my Hannah is accurate. I have the HR Hannah.

Low and behold my PO4 has been zero the entire time and my Hannah cant pick it up cause I'm not using the URL one.

Also it dawned on me.. I have no algae blooms with PO4 at 1.4, that's weird, but dinos are developing quickly.. sign of low/unregistering levels of PO4.

So my thought process is that I've spend a week or so nuking the tank with PO4-e and media to draw out every last drop of PO4. Including that from the rocks and substrate.

I've fed reef roids 3 days in a row, lightly and yesterday a full teaspoon (33g tank). My PO4 is still zero. Some of my corals were looking rough and since I started feeding roids, they have gotten much happier and moving in the right direction health wise.

Could this be that b/c I basically stripped PO4 off every surface in my tank, its "rebinding" to it as I add it back in so its not remaining in the water column to register on a test.

NO3 is testing consistently between 5 - 10ppm as a side note. All other levels are in check

 

[ColorMeGone]

If you started out with dry rock (like I did) they suck up the P04 like mad. After 11 months I'm still dosing 2ml per day Sodium Phosphate. Don't know anything about your P04e or what it might have done but once that's figured out, I would start dosing.

 

[BryanM]

I think the RODI is going to help you here.

If you decide to use lanthium do some research and be very careful. It does work quite well though

 

[Noobreefer84]

If you started out with dry rock (like I did) they suck up the P04 like mad. After 11 months I'm still dosing 2ml per day Sodium Phosphate. Don't know anything about your P04e or what it might have done but once that's figured out, I would start dosing.

yah i started with Caribsea life rock or whatever it is... dry rock painted purple.

PO4-e basically takes PO4 and binds it so your skimmer/filter sock can take it out super fast.

 

[ColorMeGone]

yah i started with Caribsea life rock or whatever it is... dry rock painted purple.

PO4-e basically takes PO4 and binds it so your skimmer/filter sock can take it out super fast.

I don't know how the painted rock absorbs phosphates but dry Marco style rock sure does.
If the stuff you put in binds the phosphates, then I would start dosing.
RODI water will be a big improvement also.. Not sure how big your tank is but I have 7 true gallons and like I said, I am still dosing P04 and N03 to keep me in check.