Magnesium deficiency???

[Smokepot]

I think I have a magnesium deficiency on this AK47....
I used plagron lightmix soil with hydroton on the bottom (and up too to avoid soil insects & two much water evaporation)
water level is always 6.4 -6.5 ph and relatively stable (in the bucket, before watering) but I didn't check the ph of the water after watering...

Last watering I used Mineral magic from GHE and a very light Flora series mix (0.25ml/l for grow, micro and bloom) and adjusted my water with some Diamond nectar (fulvic and humic acid) to have a good 6.4 pH

The staims appeared yesterday morning but the days after the plant was not as green as before....and on the evening the plants was like that....





This evening the leaves are always yellowing (inside the "skull" of the leave, not all the leave) and the teeth are curved on the top...

Is it long to "cure" the plant? or is it relatively short after giving it the good nutrients?

Thanks a lot for your help
sorry for my english...

 

[sproutco]

There is magnesium in your fertilizer. Try growing at a lower ph like 6. Test fertilizer water ph after mixing. You can test soil ph using the link in my signature.

 

[Smokepot]

My water tank is checked all time with my hanna gro check tester but I will test the ph of my soil with your method because everything else seems to be ok
Thanks a lot
have a nice evening

 

[Pablo]

this is not Mg problem but You need a PH meter.Lack of nutes maybe?What is your EC/ppm.

 

[jonnybgood29]

that looks like a combo of underfert, and over watering-ie. not enough oxygen in your rez...... why are you using soil in a hydro situation?

 

[Smokepot]

Pablo: No overwatering.....And I always have my Hanna Gro-Check (one of the best pH meter ) checking the solution pH......(The Gro-check has a seperate probe and is powered by an AC adaptor (no expensive button batteries !!! ) so I let it all time in the watering bucket...and my EC is good too
Jonnybgood : I uses soil for my bonzai mother plants (like these young ones) and hydro for my flowering system and cuttings system too...there is not only hydroton in the plastic pots...The bucket I described before is only a bucket to prepare and adjust my watering solution...

I checked the soil pH with the method Sproutco described (thanks a lot!) and it's 6.8, and it seems to be THE reason of this deficiency;
mg, iron and zinc are not very well assimilated at this pH level;So I tried a 5.5 solution this morning and the plant seems to be in a better health this evening....I hope it will be completly cured in a couple days...I don't know how long is the process...

It's a little bit overwatered now but I think it's better than having the bad results of a long period of defficiency....

here is the one of the leaves today ,it seems to be better :




Thanks for your help
Have a nice day