Making sense of Phosphate readings

[jordsyke]

I find that in my 45 gallon tank I have the same issues, I beleive that over the years the sand has just grabbed so much crap that it is forever leaching back into my system.... In my 120Gallon I use both biopellets and GFO and find a can easily keep my nitrates at 1ppm which is fine to me, and .06-.15 phosphates which is also an acceptable level in my mind