Dosing phosphate but not seeing any results, am I doing this wrong??

[OG-Goby]

I keep seeing signs of Dino’s in my coral QT tank and after testing both phosphate and nitrate were totally crashed so I decided to dose.

I bought some Trisodium phosphate from loudwolf.

Found the thread here suggesting 1.88g in 1L for a 1ml dose for a 40g to raise it .01, so I made this solution. As I have a 10g and I’m not smart, after I made this solution I diluted some by putting 75ml of RODI in a glass bottle with 25ml of the solution. This should quarter the strength if I am not wrong. Perfect as I have quarter the tank that guy has.

I know the rock will absorb some phosphate but I have dosed 5ml of the 100ml bottle 4 days in a row which in a perfect world would give me .2 phosphate but as of today the salifert test is as clear as it could be. No hint of blue.

The tank has maybe 5lbs of real ocean live rock. Does the calcium carbonate in this real rock mean it’s going to suck down more phosphate than I realized?

Should I keep dosing this? Should I do a single dose of the stronger solution?

I’d also like to “test” what I made outside of the reef. But I don’t want to waste gallons of RO doing this. So if I put some in 1L of water and test, how much of either solution would I add to get what results? As it’s a 40L tank I assume that if I put 1ml of the weaker one in it would give me about .4 phosphate. Is that right?

Sorry chemistry is just not my thing, so I am a little lost on this.

 

[*GAREEF*]

I keep seeing signs of Dino’s in my coral QT tank and after testing both phosphate and nitrate were totally crashed so I decided to dose.

I bought some Trisodium phosphate from loudwolf.

Found the thread here suggesting 1.88g in 1L for a 1ml dose for a 40g to raise it .01, so I made this solution. As I have a 10g and I’m not smart, after I made this solution I diluted some by putting 75ml of RODI in a glass bottle with 25ml of the solution. This should quarter the strength if I am not wrong. Perfect as I have quarter the tank that guy has.

I know the rock will absorb some phosphate but I have dosed 5ml of the 100ml bottle 4 days in a row which in a perfect world would give me .2 phosphate but as of today the salifert test is as clear as it could be. No hint of blue.

The tank has maybe 5lbs of real ocean live rock. Does the calcium carbonate in this real rock mean it’s going to suck down more phosphate than I realized?

Should I keep dosing this? Should I do a single dose of the stronger solution?

I’d also like to “test” what I made outside of the reef. But I don’t want to waste gallons of RO doing this. So if I put some in 1L of water and test, how much of either solution would I add to get what results? As it’s a 40L tank I assume that if I put 1ml of the weaker one in it would give me about .4 phosphate. Is that right?

Sorry chemistry is just not my thing, so I am a little lost on this.

From my experience with Salifert tests they don’t register low numbers. For phosphate test I started using Hannah checker.
Your tank might be consuming the phosphate.
I have to add phosphate nearly everyday to my system. I keep my phosphate between 0.10 - 0.15 and add between 3-5 mls of Nyos phosphate most days.

 

[BriDroid]

My nano sucks it down as well. I dose 0.4ppm trisodium phosphate daily just to keep about 0.05ppm readable on my Hanna ULR checker. I hope that one day the rocks and sand will stop absorbing it, but for now it's on an auto dose pump.

 

[ColorMeGone]

I would keep dosing a controlled amount ea. day and check once every few days to see where you're at. Don't rush it.
My Tank rock is 9 months old or so. Started out with dry rock.
I dose 2ml. per day Sodium Phosphate Dibasic and .5ml a day Ammonium Bicarbonate. 7 gallons of water. Keeps my nitrates above 10 and my phosphate at around .03 - .05.