Do you re ph the water in your reservoir?

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JadedMarxist

JadedMarxist

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Yeah I i dint clue in that you were not doing dwc.

Because my pumps are not in the water so no heat issues there not even in my tent. Lol obviously I don't use a submersible.

So do you feed then drain to waste? Or recirculate?
 
Dirtbag

Dirtbag

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Yeah I i dint clue in that you were not doing dwc.

Because my pumps are not in the water so no heat issues there not even in my tent. Lol obviously I don't use a submersible.

So do you feed then drain to waste? Or recirculate?

I do DTW in coco right now. And I dont use submersibles, but I've just found that air pumps get warm and end up pumping warm air into the airstone, which eventually starts warming up the res.
With no air pump my res stays at 68-70F. When I used to run one I always struggled to keep it under 75f.
 
cemchris

cemchris

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This is a good read on the reasoning behind (and usually the source quoted in most papers dealing with Si and horticulture) adding Si first and PH adjusting or taking the approach @Dirtbag does and you need to PH the prediluted form. You can still run into problems adding it after other nutes unless you have a real good understanding of interactions with your specific nute regiment. You could nerd out 100% and do the math if you like.

Now, in practice, I run Si at 34 ppm. Add it to the plain water in a rez and let it sit overnight. PH in the morning and then mix the nutes. I was having S precipitate out of my solution over the span of a flower cycle (buildup in the rez) and this cured a lot of that problem.

If you want the easy way follow what GH says about it. As a bonus the reasoning behind adding Calmg (containing Fe) before a nutrient that contains micros is Fe. Fe is another one of those things that's a real bitch in nutrient solutions and is very sensitive to O2 and PH. Depending on the type of chelate used for the Fe up to 50% of it becomes unavailable above 6.5 and above that starts to precipitate out and bond with other ions.. Also the reasoning behind hitting Si first ---> Ph down ---> then so on. It's mainly to control the PH of the solution before trying to dissolve other nutes into the mix, like Fe, since it is usually in the highest concentration of all micros by a long shot.

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Dirtbag

Dirtbag

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That's interesting stuff cemchris. I know/knew you cant add straight potassium silicate to a nutrient solution because at the point it enters the nutrient solution the ph spikes real high before it dilutes and can precipitate nutrients, but I've not had a problem diluting the hell out of it and adding it real slow at the end.

My only problem adding it first is I'd have to know exactly how much to add to hit my target ph. which I dont. But maybe I'll work that out and try switching things around and see if I notice a difference.

My calcium silicate FWIW, is already prebuffered and ph balanced, and it always goes in first. I really only use the potassium silicate for ph up.
 
cemchris

cemchris

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That's interesting stuff cemchris. I know/knew you cant add straight potassium silicate to a nutrient solution because at the point it enters the nutrient solution the ph spikes real high before it dilutes and can precipitate nutrients, but I've not had a problem diluting the hell out of it and adding it real slow at the end.

My only problem adding it first is I'd have to know exactly how much to add to hit my target ph. which I dont. But maybe I'll work that out and try switching things around and see if I notice a difference.

My calcium silicate FWIW, is already prebuffered and ph balanced, and it always goes in first. I really only use the potassium silicate for ph up.

Yeah and that works 100% as long as you aren't hitting above like 70 ppm total and its pretty diluted. You will know pretty quick if you solution gets cloudy after you add it in.
 
Dirtbag

Dirtbag

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Yeah and that works 100% as long as you aren't hitting above like 70 ppm total and its pretty diluted. You will know pretty quick if you solution gets cloudy after you add it in.

Oh I know the clouds.. lol, I avoid clouds in my res. it's why I stir the res so vigorously while I slowly drizzle it in, it doesnt cloud up that way. Takes me a couple mins to slowly bring the ph up.

Tonight I mixed the potassium silicate in first. Took a guess at how much was needed...
guess I got lucky!
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cemchris

cemchris

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Oh I know the clouds.. lol, I avoid clouds in my res. it's why I stir the res so vigorously while I slowly drizzle it in, it doesnt cloud up that way. Takes me a couple mins to slowly bring the ph up.

Tonight I mixed the potassium silicate in first. Took a guess at how much was needed...
guess I got lucky! View attachment 964989

Isn't it nice when it works out like that after a while? I can pretty much use a cap of AN PH down after agsil and it gets me 5.7-6.0 when its all said and done at the end.
 
Dirtbag

Dirtbag

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Isn't it nice when it works out like that after a while? I can pretty much use a cap of AN PH down after agsil and it gets me 5.7-6.0 when its all said and done at the end.

Nice. I'll keep doing it this way for a bit and see if I can hit my ph or close to it next time too. lol, was pretty cool to see 5.8 off the bat.
Nice thing about using this pbp is its pretty acidic, after adding all the nutes and two forms of silicate it doesnt need up or down. Cant complain about that.
 
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