Monday, December 8, 2008

That was Easy!

caption: Mixing Nutrient Concentrate with 8-5-16 Way back at Summer 2

My TotalGro nutrient came to the house by Big Brown today. That was pretty quick given that I only ordered it a couple of days ago (well maybe a few more than that since the invoice says December 3rd so it's been five days). A plain cardboard box containing 50# of 8-5-16 Hydroponic Special Steiner Item #2034 was delivered.

So what's that? Well it's two bags of granular compounds, one is blue and the other is white. Since the whole comes to 50# and they are used in equal measure, that works out to about 25# per bag. So what did it cost. It was shipped from Winnsboro, Louisiana by UPS to where I live in Harrisonburg, Virginia.

The nutrient cost $58.76 + $24.21 shipping for a total of $82.97. Wow, that's a lot of money, right? Not really. The problem is that it is the minimum order, but when I use the nutrient I tend to use only about 5#'s of each per year and that's for large system with 42 plant sites (nominally). When you spread the cost over five years it is only $16.60 per year. If you check out the cost of liquid nutrients you'll find that that is dirt cheap.

What do I do with it? It's a simple two step process:
1) Step 1 is to make a concentrate of each of the two different solutions. I mix about 15 oz of blue in a gallon of water to make the blue solution, and 15 oz of the white to make a gallon of white solution. These are both concentrated. You don't use them on plants at this concentration.
2) Step 2 add equal amounts of blue and white concentrates to your nutrient tank water until you get the conductivity you want to run at. A standard conductivity of about 22 CF is produced by mixing about 1 oz of each concentrate per gallon of working solution.

You check the solution strength regularly topping off the tank with fresh water and adding concentrate to bring the tank back to the right conductivity. I have never seriously messed with pH. If you have a pH problem you may have to do that. It's not too much more complicated, but you need additional solutions and instrumentation so I would try to get by without it if possible.

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