Po4 export - how much do I use?

[crawdads57]

I finally tested for phos. I had never tested any tank for phos before, so I was not looking forward to it. So I think I'm running about 1.0 to 1.5ppm. That is not good, but on the scale of not good and super bad I'm not sure where 1.5 really falls. My nitrates run less than 7.5, more like 5ppm.

 

So I bought some po4 export because I don't have a reactor or a place to put one. This seemed like a good choice for use in a HOB which is where it will go alongside my carbon. But I'm not clear on the instructions. It looks like I'm going to only use 1 or 2 cubes at a time? Does that seem right? It's a total volume of 15 to 16 gal.

[metrokat]

That seems right. Weigh it and use what they say. I use 7-10 stones in my ~60 gallon system.