Dosing Instructions for Brightwell Aquatics NeoPhos.

[DivingTheWorld]

I'm planning to eventually move to a less expensive Phosphate supplement, but for now I got a bottle of NeoPhos. Here are the instructions that I've found on various posts around Reef Central as well as the company's website:

1 ml NEOPHOS will increase the phosphate concentration in 1 US-gallon (~3.8 L) by ~1.2 ppm; 1 drop from plastic bulb pipette (enclosed within bottle) will increase the concentration in the same volume of water by ~0.06 ppm.

My system is approx. 89g, so my calculation would be 0.74ml of NeoPhos to raise my tank Phosphate 0.01ppm.

1.2 / 0.01 = 120. 89ml / 120 = 0.74ml

On the bottle, it has a completely different set of instructions which reads:

1 ml NeoPhos will increase the phosphate concentration in 1 US-gallon (~3.8 L) by ~0.05 ppm.

89ml / 5 (0.01 ppm) = 17.8 ml

Also on the bottle it says:

Multiply tank capacity in gallons x ppm increase desired x 18.9 - ml of product to add. Example to raise the concentration of phosphate in a 25 gallon aquarium by .01 ppm, the calculation is: 25 x .01 x 18.9 = 4.7 ml or about a capful. (a capful is 5 ml)

89 x .01 x 18.9 = 16.821 ml

Seriously, how sketchy can the instructions on one product be?? :headwally:

My phosphate as of this morning around 6:00am was 0.0031 ppm (crazy low for acros).

I chose to go with the bottle instructions but a little low, so dosed 15ml NeoPhos.

My phosphate as of this evening around 4:30pm was 0.0215 ppm.

I'll test again tomorrow morning at 6:00am, but based on this, I would say the correct formula to raise 0.01 ppm should be at most:

gallons x .01 x 8.41 = ml NeoPhos

[bertoni]

I'd try the larger dose on a 1g sample of saltwater. I don't know exactly what's going on with the numbers, but they don't agree, so I don't trust any of them. 1 ml should be fine. The water should be okay for small water changes, especially if diluted a few times with cleaner saltwater.

[DivingTheWorld]

I'd try the larger dose on a 1g sample of saltwater. I don't know exactly what's going on with the numbers, but they don't agree, so I don't trust any of them. 1 ml should be fine. The water should be okay for small water changes, especially if diluted a few times with cleaner saltwater.

I'm a cowboy (kidding) so I went ahead and dosed directly into the tank yesterday morning. I was actually worried all day yesterday that I would come home to a dead tank, but it worked out. Here's what I dosed and the testing results:

Reading 5:30am 06/19 0.0031 ppm, dosed 15ml NeoPhos (89g system)
Reading 4:30pm 06/19 0.0215 ppm
Reading 5:30am 06/20 0.0092 ppm, dosed 15ml NeoPhos

[reefgeezer]

I'm a cowboy (kidding) so I went ahead and dosed directly into the tank yesterday morning. I was actually worried all day yesterday that I would come home to a dead tank, but it worked out. Here's what I dosed and the testing results:

Reading 5:30am 06/19 0.0031 ppm, dosed 15ml NeoPhos (89g system)
Reading 4:30pm 06/19 0.0215 ppm
Reading 5:30am 06/20 0.0092 ppm, dosed 15ml NeoPhos

I can't help you much on how much to dose but...

What is the accuracy of the test kit/instrument you are using? Does it read phosphate to 4 decimals? I ask because I wonder how much of what you are seeing is noise. For example, I use a Hanna 736 ULR. It's accuracy is +/- 5 ppb phosphorus or after conversion (I think) +/- .015 ppm phosphate. I would be hesitant to make decisions using my Hanna meter when the readings were close to the advertised accuracy.

FWIW, I don't think there is a certain number you need to hit. I think that any positive number indicates that there is inorganic phosphate available for the flora and fauna that need it. I like to have something above my meter's accuracy so I chose .03 ppm. That means my level is somewhere between .015 and .045 ppm. I don't even do the conversion anymore. I just look for something near 10 ppb.

[Dan_P]

Test the dose by adding the estimated amount for one gallon in a one gallon sample of tank water and measure the actual level. There is no reason to guess which is the correct interpretation of the instructions or to test it full scale.

[DivingTheWorld]

Test the dose by adding the estimated amount for one gallon in a one gallon sample of tank water and measure the actual level. There is no reason to guess which is the correct interpretation of the instructions or to test it full scale.

Guessing is done, results attained.

[DivingTheWorld]

I can't help you much on how much to dose but...

What is the accuracy of the test kit/instrument you are using? Does it read phosphate to 4 decimals? I ask because I wonder how much of what you are seeing is noise. For example, I use a Hanna 736 ULR. It's accuracy is +/- 5 ppb phosphorus or after conversion (I think) +/- .015 ppm phosphate. I would be hesitant to make decisions using my Hanna meter when the readings were close to the advertised accuracy.

FWIW, I don't think there is a certain number you need to hit. I think that any positive number indicates that there is inorganic phosphate available for the flora and fauna that need it. I like to have something above my meter's accuracy so I chose .03 ppm. That means my level is somewhere between .015 and .045 ppm. I don't even do the conversion anymore. I just look for something near 10 ppb.

I also use the Hanna 736 (+/- 0.015 ppm). I can tell you from doing back to back test on multiple occasions though that it's a very accurate tester. The only variance I've seen was 1 ppb. If you're aware of a more accurate phosphate test for a reasonable price, I'm all ears.

Here's what I can tell you for sure: My tank read 0.00 for two weeks in a row and my acros started getting burned tips and my montis started crapping out. The general consensus for acros seems to be 3-5 Nitrates and 0.03-0.05 Phosphates and I've noticed that's when my sps look best. My Nitrates are there and I'm just trying to get my Phosphates back up. Within the last 4 days I've seen noticeable improvement in my Montis and Acros since getting my Phosphates up.

But all this is besides the point. The point of the thread was to help others with better dosing instructions for NeoPhos based on my own experience, not decide if they should use it. Clearly at least some of their instructions are totally bogus.

[DivingTheWorld]

Dosing update:

Reading 5:30am 06/19 0.0031 ppm, dosed 15ml NeoPhos (89g system)
Reading 4:30pm 06/19 0.0215 ppm
Reading 5:30am 06/20 0.0092 ppm, dosed 15ml NeoPhos
Reading 3:30pm 06/20 0.0215 ppm
Reading 6:30am 06/21 0.0153 ppm, dosed 15ml NeoPhos

It looks like the system is starting to hold phosphate a little.