Phosphates

[Spdjnky]

I am using TriSodium Phosphate Anhydrous-TSP
how long should I wait in between tests I am still not getting phosphates after dosing 15 Mi's

 

[WIReefer]

I would wait 15 mins had the same problem took me a while to see it rise.

 

[Spdjnky]

I would wait 15 mins had the same problem took me a while to see it rise.

thanks I have been giving it a couple hours but this is driving me crazy I've got it up a few times to .02 ppm but then it goes right back to zero again the next time I check it.

 

[WIReefer]

thanks I have been giving it a couple hours but this is driving me crazy I've got it up a few times to .02 ppm but then it goes right back to zero again the next time I check it.

That’s pretty normal! Took me months of dosing and checking to get it stable where I wanted it to be! Just remember nothing great happens fast!

 

[Randy Holmes-Farley Verified Community Expert]

It may take vastly more than the calculated amount as lots of added phosphate will bind to rock and sand.

 

[dtrick]

It may take vastly more than the calculated amount as lots of added phosphate will bind to rock and sand.

Is it possible that binding to the rock/sand can also reverse into leaching phosphate from the rock/sand? I am dosing daily 10ml of trisodium phosphate solution that is close to OPs calculation for a 65 gallon tank. I have tested 15 minutes after dosing and get over 0.10 and test 24 hours later and usually get around 0.02. My tank is new at just over 3 months old. Is there a danger with dosing this amount daily?