At my last course I had an old SDI sprayer that plumbed the circulation water up to the strainer basket, so that when you added your water soluble fertilizers to the tank, the strainer screened any chunks out, as the circulation water dissolves it. Simple with no slurries needed.
I had it set up to where I could weigh out whatever custom analysis I wanted using urea, mono ammonium phosphate, sulfate of potash, ferrous sulfate, mono potassium phosphate, potassium nitrate, ammonium sulfate, magnisol, etc. and it all went in to solution very easily. Anyways, the cost was less than a third of the prepackaged liquid formulations and there is NO WAY you could ever tell the difference - especially when you are using growth regulators. And it was safe,. And there was no extra labor involved because it went out with the standard fungicide applications. I think it even made the fungicides more effective.
I have been told that you can go all the way up to 1 lb of water soluble product per gallon of water, but I don't think I ever put more then 1 pound per 2.75 gallons solution.
Now I have a Toro Sprayer and it takes forever to put water solubles in to solution.
Well as far as I know, SDI is the only sprayer that is set up so that you can spray water solubles easily. But if you havethe right sprayer you can save a lot of money and have some really nice turf for the bargain. Heck I don't think the grass knows the difference.