V8.9 take 1
Mixing order:
- 4.675 g calcium nitrate in about 90 mL water -> dissolves fine
- 6.273 g urea phoshate added -> slightly milky, almost entirely dissolved?
- 8.646 g ammonium sulfate -> partially dissolved, very milky
- Water added to ~200mL -> still very milky (250 mL would have been 500:1)
- Water added to ~400mL -> still milky (500 mL would have been 250:1)
- Water added to ~800mL -> still milky (1000 mL would have been 125:1)
I guess I’m no longer getting calcium phosphate precipitate due to using urea phosphate, but I still get calcium sulfate precipitate.
I guess I should’ve added the other salts first, to prevent calcium sulfate precipitation. With more nitrate in solution, there would be less chance for the calcium to bind with sulfate.
V8.9 take 2
Mixing order:
- 11.13 g potassium nitrate in about 90 mL water -> takes a while to dissolve, but does dissolve ok
- 2.334 g calcium nitrate added -> dissolves ok
- 2.635 g magnesium nitrate added -> dissolves ok
- 3.317 g urea phosphate added -> dissolves ok, slightly milky but no precipitation after a minute
- Water to ~200 mL
- 4.322 g ammonia sulfate -> dissolves ok!! Very slightly milky but no precipitation after a minute
- 0.935 g trace elements -> formed some chunks, but after breaking up dissolved ok
Success! It’s only a 250:1 solution but at least there’s no precipitation any more. This is the most concentrated 1-part hydroponic fertiliser I’ve made so far.
V8.9 take 3
- 22.26 g potassium nitrate, 5 g calcium nitrate, 5.274 g magnesium nitrate in about 200 mL water -> dissolves ok (I dropped half the calcium nitrate, put most back but added half a gram to compensate, ughh)
- 6.273 g urea phosphate added -> dissolves ok, slightly milky but no precipitation after a minute
- 8.64 g ammonia sulfate -> dissolves ok!! Very slightly milky but no precipitation after a minute
- 1.872 g trace elements -> again some small chunks but dissolves ok
However, after a few minutes precipitation does start to form. 500:1 is too much, I guess 250:1 is the best I can do with this amount of sulfate.
What’s next
250:1 is already nice, it’s more concentrated than GT Foliage Focus which is 150-200:1. However there are more concentrated products such as Canna Floragro and Dyna-Gro Foliage-Pro (both around 800:1). Liquid Gold Leaf (500:1) is the only one with significant amounts of sulfur, though – I wonder how they do that. Maybe a chelator.
For V9 I will look at either lowering sulfate concentration to get to 500:1, or using a different form of sulfur. I could get some biosulfur (mostly S8), I wonder how soluble that is.
Edit
Shit, even the 250:1 eventually started precipitating out something. Probably calcium sulfate. Back to the drawing board.