Hydro/DWC Issue

[Chris1]

I've been having this problem for about 2 weeks, changed the res and bumped PPMs and nothing really changed, only on a couple leafs...

Ph has been 5.8 all week, the previous week it was dropping

PPMs started at 675 (6 days ago), today they are around 550 (with 2 seperate top ups with nutes)

 

[smokestack23]

cant really see much in those dark pics. What kind of water? Mg def?

 

[hippydan]

I'd agree it might be Mg deficiency, however with no information the best answer you're going to get is going to be a guess.

 

[Chris1]

Hi sorry...


Gh 3 series (with hardwater micro), floralicious plus and liquid koolbloom. Using tap water with no cal mag, PPMs are about 175 from the tap.

 

[Growdoc]

this is a MG def, use a MG supplement in your next 3 waterings

GrowDoc

 

[Chris1]

So I just need a bottle of calmag? Or straight mag? Can you recommend what to use, I'm running the GH line with hardwater formula

 

[Chris1]

And what strength? I do not have a water analysis of my tap, but the ppms start at 175 from tap

 

[DigDuggreen]

i just realized what your problem is.... your using hard water micro, use the regular and I beleive that will solve your problem. im running the same stuff and Im right about the same stage you are, my tap water is also about 175-200 ppm's and im running regular micro, the cal/mag in the hard water micro is less and that is why your deficient. I bet you anything. Im at day 33 and I have not had to add any cal/mag at all. and Im leaning on calcium def. not magnesium in your situation. hit me up if you want to chat more about it.

 

[GoozMan]

Just one more voice in agreement. I was using RO water with that same GH Hardwater Micro just because I had it, and I suffered serious deficiencies in yield by the end of the grow. I got a bottle of General Organics and followed the instruction on the back for light feeding = 1 tsp/gallon.

 

[Chris1]

Thanks everybody, I grabbed a bottle of Cal/Mag by GH, I'm gonna run it very lightly and see if that clears up the leaf issues.

 

[FreezerBoy]

i just realized what your problem is.... your using hard water micro,

Bingo.

However, that only get's us halfway there. No one pH reading allows equal absorption of all nutes. By maintaining a flat pH level, you guarantee an unbalanced feeding. Worse yet, 5.8 is the one number that locks out MG, the very deficiency we're dealing with.

In a healthy res, EC and pH move in opposite directions. By barely under or overfeeding, we can force pH to swing at our discretion. Create a pH swing between 5.5-6.0 (some here vouch for as low as 5.2), lose the HW Micro for regular and your problem should disappear

pH and Nutrient Absorption Chart - HYDRO:

How pH Affects Plant Nutrient Uptake (same as above in English):

 

[Chris1]

Thanks FreezerBoy and everyone else who helped, I snagged a bottle of GH CalMag and gave a very light feeding, I'll see if that helps. Is it cool to switch from HW Micro to reg Micro mid flower?? I'm at day 40