Raising PO4

KenO · Jan 18, 2018

I just started dosing TSP. I started with testing using it dry. Once I figured out what my tank needed I made up a liquid solution. I have my doser adding it once every few hours now. PO4 level is now staying at .08. It's been about a week now and I've noticed the colors of my corals have improved. I have a scrubber which quickly consumes my NO3 and PO4.

Rick Gaas · Jul 4, 2018

Randy, any place I should be able to find food grade trisodium phosphate locally? Lowe’s, Walgreens???

Velcro · Jul 4, 2018

I've dosed phosphate in the past because of consistent 0 reading on the hannah ULR phosphorus reader. If I dose or feed more I start getting some algae on the rock. I stopped dosing and stopped check phosphorus for now and just watch the hair algae. If it starts to take off I slow down on feeding. If it looks like it's going away I bulb up the feeding a bit. Got sick of chasing a number.

That being said I'm starting to question the value of the inorganic phosphorus result from test kits. I think it's just more of a feedback for how much youre feeding/exporting, not necessarily a super important number that you have to have at a certain number.

I still read 0 whenever I check and i feed a LOT. only export is a skimmer, chaeto and 1% daily water change. According to some, a zero reading would mean dead coral. Here are some pics of what 0 ppb P looks like in my tank. As you can see I have some algae and some colorful coral.

Rick Gaas · Jul 4, 2018

Velcro, what level is your NO3? Why the algae? Thank you!

Velcro · Jul 4, 2018

Rick Gaas said:
Velcro, what level is your NO3? Why the algae? Thank you!

I haven't checked them in several weeks. Like I said, I really feed the tank. That amount of algae doesnt bother me at all

DirtDiggler2823 · Jan 19, 2020

Velcro said:
I haven't checked them in several weeks. Like I said, I really feed the tank. That amount of algae doesnt bother me at all

How are you dosing phosphate, and do you have any critters that eat algae in your tank?

Randy Holmes-Farley · Jan 19, 2020

DirtDiggler2823 said:
How are you dosing phosphate, and do you have any critters that eat algae in your tank?

Are you asking what chemical or what mechanics?

DirtDiggler2823 · Jan 19, 2020

Randy Holmes-Farley said:
Are you asking what chemical or what mechanics?

Kind of both. His method of dosing, as well as which salt he was using. I see some are dosing straight powder, and others are making a solution with RODI water. Someone even asked about mixing their solution in their NOPOX, if I read it correctly. I'd much rather make my own phosphate additive, than buy one on the market, but I need to understand the chemistry behind it a bit more.

Randy Holmes-Farley · Jan 19, 2020

There’s no reason to dose the powder and I don’t know of anyone who does.

Some use dosing pumps, but once a day manual works fine.

the best chemicals are good quality sodium nitrate and phosphate, or potassium versions.

DirtDiggler2823 · Jan 19, 2020

Randy Holmes-Farley said:
There’s no reason to dose the powder and I don’t know of anyone who does.

Some use dosing pumps, but once a day manual works fine.

the best chemicals are good quality sodium nitrate and phosphate, or potassium versions.

I will look for good sodium phosphate compounds then. Thanks Randy!

Theo_0 · Sep 2, 2020

If you use the potassium phosphate monobasic, is there a specific amount that you should mix and a specific amount to add per gallon? @Randy Holmes-Farley

Blammomike · May 17, 2021

Randy Holmes-Farley said:
For example:

https://www.loudwolf.com/store/index.php?main_page=product_info&products_id=197

Randy, can all of these products be used for the same formula to make a dosing solution? Or do they differ?

Randy Holmes-Farley · May 17, 2021

For our purposes, where highly exact dosing doesn't even make sense since so much will be bound to rock and sand, this calculator is adequate for any sodium or potassium phosphate. Just alter the dose up or down going forward as needed. Use the entry for "phosphate from potassium phosphate"

James' Planted Tank - Dosing Calculator