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Old 10-14-2009, 02:41 AM
Luches Luches is offline
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Join Date: Jul 2009
Posts: 177

You're most welcome!

Originally Posted by Errol View Post
You're spot on. The reading at 1.8 is now about 6.3. I've added MgSO4. by the way, but not the calcium chloride for the moment because it's only available in very large bags at a very high price.
6.3 is fine if growing various plants - it will probably climb though, as uptake of acid components is supposed to be faster. Watch it happen ...
About the calcium chloride: it's necessary if your tap (or source water) hasn't got much calcium. What's the EC reading of your tap water? If it is between 0.1 and 0.2 (like mine), very little calcium is contained. If it's between 0.3 and 0.4 there should be 30-40 PPM of calcium contained anyway and calcium chloride isn't really needed. Please keep in mind that previously with your higher calcium nitrate content, you got lots of calcium too! Try to get a better source, specialized drug stores should have it in 1kg packages. I only pay about 1 USD $ per Kilo, food grade!

Originally Posted by Errol View Post
I also came to an interesting realisation - when I first started out in hydroponics, my local supplier simply told me to use Hydrosol and calcium nitrate '50/50' which I took to mean equal quantities. But your formula is based on equal weight, and there's a difference. The calcium nitrate I use is 11% heavier than Hydrosol, which means a 10% reduction in it (using a weight-based mix) for starters.
They say: If the terrain differs from the map, stick with the terrain!

Originally Posted by Errol View Post
Factoring this into your formula, I think my plants will be getting 35%-40% less N this year. I'll be keen to see the results.
Not sure about that percentage... let me check something...

Don't see me as a maniac, but you have to consider the actual EC versus gram/liter ratio of each component, to know how much less Nitrogen you use with the new mix

Mixing 1 Gram of Calcium Nitrate in 1 Liter of water, will result in 0.95-1.0 EC, while mixing 1 Gram of Magn. Sulph. in 1 Liter, will only give a reading of EC 0.66-0.70. You can "try that at home", but you'll need an accurate scale to do so. The ratio of Hydrosol has to be seen as an estimate, though. I haven't had Hydrosol handy and had to guess its composition in components to get to that number (0.76). In case you'll measure it, keep me posted if my estimate was accurate!

Originally Posted by Errol View Post
PS I've uploaded a few photos to an album if you're interested in having a look at my setup.
Sure thing, glad to see it - I haven't found your post yet, will check again now...


Last edited by Luches; 10-14-2009 at 03:01 AM.
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