How much grit are you getting? sounds like a lot.

I use the same stuff and maybe get a 1/2 teaspoon worth of grit on the bottom (no fitter on pump 12gal res) by the end of the month.

I tend to add each nutrient in a 2 gallon bucket of R/O water (mix/dissolve) and then add to the main tank within minutes of each other (aim for 600-700ppm total and redo around 350ppm). Also have an air stone going maybe that might help keep it dissolved?

This post was edited by Newguy27 on Sat, Jul 5, 14 at 14:32

Adding dry chemicals to a large quantity of cold water is hit and miss. I would make up 3 seperate concentrated stock solutions so the chemicals are already fully in solution before adding them to the res. You can use warm/hot water for the stocks which will help to dissolve the chemicals.
If you see grit in the stock solutions i would consider changing nute brands, ideally hydro nutes should be fully soluble and crystal clear.
Here`s my nutes before they go into the tank and in the runoff container after passing through the aero system. The ec and ph changes but not much else.

This post was edited by hex2006 on Sun, Jul 6, 14 at 12:21

I use the same stuff. Seems like mixing master blend, then magnesium, then calcium nitrate seems to help.

Thanks for the replies.

So far we don't use enough nutrient to need bulk tanks. But I know that works.
We currently dissolve in Luke warm water then add.
I will try that order!
Did a nutrient change on a 50 gal res due to a leak and it didn't do it this time. So not sure.

The other issue I am having with masterblend is mixing masterblend and cal nitrate at a rate of 10g per 5 gallons I am only getting around 350 ppm addition to my tank. Assuming of course my ppm meter is working properly.

Does this sound right?

10g of calcium nitrate (tetrahydrate) in 5 gals should give you an EC around 0.4, if you`re using Calcinit it`ll be slightly higher at 0.5.
I dont use bulk tanks, the most i mix at any one time is 25L :)

This post was edited by hex2006 on Mon, Jul 7, 14 at 12:08

Rio - I got a formula from MHP Gardner and his is 12 mb, 12, Cal N, and 6 Epson Salt. Someone asked him the same question. "Is that enough". He said its plenty, but I still double that formula because my ppm came out to around 800. I have large squash plants, cucumbers, and tomatoes running in 10 5 gallon dutch buckets with a 27 gallon reservoir and the plants are doing amazing.

^ Like he said MHP ratio works (think it was around 350ppm when I did it) but it doesn't hurt to add a bit more mainly b/c most plants that demand nutrient (anything that fruits) can suck up those nutrients fast.

*I think that video were he gives that formula (12g 12g 6g per 5 gal) he was doing lettuces a low depending plant.

This post was edited by Newguy27 on Mon, Jul 7, 14 at 14:39

Ok, we may go to 12 then, our lettuce looks amazing, but we have a lot of it now. 300 plants on a 55gal res. nutrient changes come once every 2 weeks under this load.

The 12/12/6 nute mix (N: 100, P: 50, K: 200, Mg: 33.5, Ca: 107 ) will be depleted pretty rapidly by tomatoes, Keep an eye on the ppm drop as you may need to add back at full strength and/or change out the res more frequently to avert potential deficiency issues.

Is there any health hazard consuming veggies/herbs produced using Masterblend as a fertilizer?