Sodium Nitrate Dosing...Help!!

[rock_lobster]

It's contradictory at all. There's no mechanism by which adding nitrate directly reduces nitrate. As I said in my post, it's possible that something is nitrate limited and adding nitrates will give it the nutrients it needs to grow. But that's far from a guarantee.

It's not smart to assume that dosing nitrates will reduce phosphates because there's no direct mechanism or pathway to do that. If you'd like to claim that in a lot of cases it does, you're probably right and I don't take issue with that. But we should not be telling people that dosing nitrates will reduce phosphates because it just doesn't.

In every tank I've ever dosed nitrates into (that had zero detectable nitrates) phosphate always decreased rapidly. I've done at least 30 tanks that were low nitrate and needed to start dosing. I think its safe to say that dosing nitrates will likely reduce phosphate (indirectly) and it would be a very good idea to have some on hand. It would be very bad advice to tell people that dosing nitrates will have no effect on your phosphate levels because it most certainly will and it doesnt hurt to have phosphate on hand and a phos checker to be prepared.

 

[BluewaterLa]

Both members have very valid points and good advice here, Without getting the tread muddy here I will place my 2 cents into the pot ( adjusted for inflation of course ).
I see two persons offering good advise with solid thoughts here, more or less conversing over the same Difference if you will.
One is stating that Dosing Nitrate has NO direct effect on reducing Phosphate which can be seen as true
The other is stating that Dosing Nitrate will not directly lower Phosphate, Which also can be true, Hence the same difference argument.

No one said NOT to test for Phosphate and keep an eye on it while dosing Nitrate to any system which is solid advise.
You can view this from both sides of the fence in that Dosing Nitrate into a Nitrate deficient tank being the only limiting nutrient or main one that once dosed organisms of all walks will begin to utilize the Nitrate and Phosphate again for growth, thus reducing Phosphate levels.
To what point of reduction highly depends on the system, No disagreement here I would suppose.

The other way of looking at this is that Dosing Nitrate to a system that is NOT void of Nitrate but undetectable levels due to organisms consumption would more than likely NOT see a reduction in Phosphate levels due to the growth Still being present in the system ( nutrient in / Nutrient out )

Either way the most important thing with anything we do with our reefs is to test often and make small slow adjustments as needed for our particular system needs.
Good thread with good advice and experiences shared here.
Thanks to all who have contributed thus far.

 

[BluewaterLa]

I mixed my sodium Nitrate as follows.
500 ml RODI water
50 grams Sodium Nitrate.

This mixture allows me to dose 240 gallons of water volume with 20 ml to Raise Nitrate 1 ppm.
May be slightly over 1ppm but not significant.
Anyone can play with the numbers to achieve a mixture and dosage tailored to their size tank.

 

[chevythang92]

My phosphate had been .33 using the hana low range test kit and my nitrates are 0 using the red sea test kit. Recently I was able to get my phosphates down to 11 . When I feed my corals it shoots back to 24 then goes back to 11 in a couple of days.i didn't test nitrate right after feeding but they are at zero still when I did check.So my question is by me adding sodium nitrate would that raise my nitrate and lower my phosphates at the same time ? As long as I keep my phosphates above .03 I should be ok and I can dose nitrate straight to 5 if I wanted to with no ill effect if I knew how far that would drop my phosphates.

 

[Evaaron]

Randy is their any concern in mixing KNO3 and NaNO2?
I am currently dosing KNO3 and want to switch to NaNO2 but dont know I can just start adding the NaNO2 to the dosing container without a reaction of some sorts.

 

[ScottB]

My phosphate had been .33 using the hana low range test kit and my nitrates are 0 using the red sea test kit. Recently I was able to get my phosphates down to 11 . When I feed my corals it shoots back to 24 then goes back to 11 in a couple of days.i didn't test nitrate right after feeding but they are at zero still when I did check.So my question is by me adding sodium nitrate would that raise my nitrate and lower my phosphates at the same time ? As long as I keep my phosphates above .03 I should be ok and I can dose nitrate straight to 5 if I wanted to with no ill effect if I knew how far that would drop my phosphates.

At least that is my experience. Dosing nitrates lowers my PO4 every time -- even allowing for test kit error. Maybe it won't for you, but I would keep an eye out.

 

[PatW]

I use .5 cup of crystals in a gallon of RODI for a stock solution. I dose a tablespoon or two in a 300 gallon tank. For smaller tanks, like a 100 gallons, the dose would be a teaspoon.

The dosage you use would depend on your export of nitrates, your systems uptake, and the amount you add in food. So it will take awhile fooling around with the amount you add to figure out the right amount.