Confirm Mag deficiency

[alexcarter]

Good evening everyone.I have some plants showing what I believe to be Mag def but am not a expert in any means and am hoping for some confirmation or alternative suggestions.The facts:
I have blotcy light green spots on leaves that progress to very light green and also very purple stems.I am growing in pro mix bx in 4 gallon pots.Several strains are afflicted .Well water Ph is 7.6 I bring it down with Ph down to 6.25.I did water a few times a few weeks back with the 7.6 water but have only used 6.25 since.There is 250 PPM TDS in the water .I use General Hydroponics 3 part flora series as follows :50ml micro/50ml gro/50ml bloom in 12 gallons of water.It reads about 680-710 PPM.The temperature in grow area is 28 with lights on and 22 lights off.RH is steady 45.I have some plants in veg showing this leaf discolor and damage and some in flower showing same issue.The first pic is rockstar 4 weeks in veg (it starters off very subtle like second photo).The second photo is a 2 week in veg Bubba Clone show the discoloring starting.The third pic is the whole rockstar plant.Any confirmation or advise appreciated.
Thanks.

 

[oldfogey420]

Calcium and magnesium deficient in my opinion. And a little too much N perhaps.

 

[kingtitan]

250 PPM plain water has enough cal/mag.

The PH is way off for the soil less medium (promix is hydroponic) and you are locking out. You need to flush the pots with at least 6-8 gallons plain water PH to 5.5 - 5.7 then water with about 2 gallons of PH 5.5 nutes.

 

[alexcarter]

250 PPM plain water has enough cal/mag.

The PH is way off for the soil less medium (promix is hydroponic) and you are locking out. You need to flush the pots with at least 6-8 gallons plain water PH to 5.5 - 5.7 then water with about 2 gallons of PH 5.5 nutes.

View attachment 4051097

I flushed pretty heavy a few days ago.If I measure run off after a good watering of ph 6.2 the run off is measuring 5.8 ph.If I get that down to say 5.6 then water with nutes at 5.5 I should be good?

 

[leather lungs]

Magnesium deficiency

 

[kingtitan]

I flushed pretty heavy a few days ago.If I measure run off after a good watering of ph 6.2 the run off is measuring 5.8 ph.If I get that down to say 5.6 then water with nutes at 5.5 I should be good?

Are you using straight ProMix BX with mycorrhiza? usually with pro-mix I water in 5.6-5.7 and get run off around 6.3ish with the lime buffer in the mix already, though I do use HP. The range you are getting is correct for the medium regardless. If BX is anything like HP the PH wont budge a whole lot once it stabalizes, you want to water with 5.5 water and then as the medium dries the PH will swing to 6.3-6.5 giving you the full range of nutrient availability during the week watering (if they dry out in 1-3 days then just plain water until the next week). Don't let Pro Mix get bone dry between watering, check by weight.

Check the run off so its not going below 5.5 as you say your BX is swinging towards acidic, if it stabilizes at 5.8 your are gold.

Also don't panic and take it slow, don't try to do everything in one go, its not going to die overnight or anything. Smoke a bowl and chill

 

[andy s]

ive used promix for the first time on my last run and current clones and it makes me have deficiencies and i hate it lol. ph i good, it micro nutes like boron or something and sometimes mag

 

[andy s]

with other soils i can let em go for a month no feeding but this stuff 2 weeks in and i have to feed or im spending a week correcting issues

 

[kingtitan]

with other soils i can let em go for a month no feeding but this stuff 2 weeks in and i have to feed or im spending a week correcting issues

You need to treat it like Hydro not Soil (dirt). The medium needs nutes every time you water after it gets dry, if its not drying out in a week then the pot is too big, if its drying out too quick then water with plain once or twice before nutes again.

 

[andy s]

You need to treat it like Hydro not Soil (dirt). The medium needs nutes every time you water after it gets dry, if its not drying out in a week then the pot is too big, if its drying out too quick then water with plain once or twice before nutes again.

i mix it. each part lets say its a solo cup
1 part perlite
1 part peat moss
2 parts ffof
4 parts promix
1 part earthworm castings
then i add rooting horomone into my soil and mix it real good
small pots take 3 days exactly to dry, my 3 gallons take 4 days and i let them get really dry..

 

[whitebb2727]

I flushed pretty heavy a few days ago.If I measure run off after a good watering of ph 6.2 the run off is measuring 5.8 ph.If I get that down to say 5.6 then water with nutes at 5.5 I should be good?

Hmm. Looks dry to me. Try watering a little more often. Dial the nutes back a hair and water, feed, water, feed etc. Water until good run off.

On second look it looks like the soil has dried to the point of pulling away from the pot.

Peat based products are bad for that. It dries fast and the drier it gets the harder it is to take water. It will run down the sides.

If it is pulled away from the edge work the soil and work it back to the sides and water good. I water in stages. Once lightly and then heavier about 10 minutes later.

I'm not 100% sure its mag but a dose of Epsom salt wouldn't hurt it.

 

[kingtitan]

Hmm. Looks dry to me. Try watering a little more often. Dial the nutes back a hair and water, feed, water, feed etc. Water until good run off.

On second look it looks like the soil has dried to the point of pulling away from the pot.

Peat based products are bad for that. It dries fast and the drier it gets the harder it is to take water. It will run down the sides.

If it is pulled away from the edge work the soil and work it back to the sides and water good. I water in stages. Once lightly and then heavier about 10 minutes later.

I'm not 100% sure its mag but a dose of Epsom salt wouldn't hurt it.

I was going to suggest 1/2 tsp epsom in 1 gal water as foliar spray but I didn't want to overwhelm him or the plant right now and to focus on fixing that PH so that he gets the rhythm of the 5.5-6.5 swing game.

 

[kingtitan]

i mix it. each part lets say its a solo cup
1 part perlite
1 part peat moss
2 parts ffof
4 parts promix
1 part earthworm castings
then i add rooting horomone into my soil and mix it real good
small pots take 3 days exactly to dry, my 3 gallons take 4 days and i let them get really dry..

Ok, that is amended so the hydro rule doesn't apply to that. I don't know a whole lot about soil grows myself. If the OP is using his pro mix BX with anything else then my suggestions do not apply.

 

[whitebb2727]

I was going to suggest 1/2 tsp epsom in 1 gal water as foliar spray but I didn't want to overwhelm him or the plant right now and to focus on fixing that PH so that he gets the rhythm of the 5.5-6.5 swing game.

I don't foliar spray. I just add it to my water.

 

[alexcarter]

Thanks for the all the guidance everyone.
I am going to give them another good ph adjusted watering tonight and see how things go.

 

[polishpollack]

You probably don't need to pH your water. Even though it's become very common to do this, 7.6 doesn't need to be adjusted. Your ferts will lower pH and using low pH water keeps your soil more acidic than it should be. Your ppm level is rather high for a soil grow. Don't feed every watering. Your leaves don't look like mg def. They look like over fert. Dark green with dying leaf tips sure looks like over fert. Plan on transplanting to large containers, like 15 gallons or bigger in the future if possible.

 

[andy s]

You probably don't need to pH your water. Even though it's become very common to do this, 7.6 doesn't need to be adjusted. Your ferts will lower pH and using low pH water keeps your soil more acidic than it should be. Your ppm level is rather high for a soil grow. Don't feed every watering. Your leaves don't look like mg def. They look like over fert. Dark green with dying leaf tips sure looks like over fert. Plan on transplanting to large containers, like 15 gallons or bigger in the future if possible.

? first ive ever heard.
your soil has its own ph, it will change when wet depending on what you add and will change again when the soil drys out. if you always water your medium with water with a ph of anything greater than 6.5 youre gonna have issues at some point in your grow bc of it. the more you water with a higher ph the higher your soils ph will get.not all nutes are the same not all peoples water is the same, for examle, my water comes out at 7.8 from the tap, i ph it to 6, add my nutes and it raises the ph lvl of the water. ive used other nutes and theyve made it go down but never in perfect range. marijuana likes a more acidic soil anyways friend. most nutes cant be properly absorbed at a high ph range. i wouldnt suggest that to other growers what might work for you going against the standard doesnt mean someone should be tough bad practices imo. silica is another example, itll make your ph drop way down. if you dont ph you wouldnt know.. then youre left wondering wtf happened. lol. superthrive is another additive that drops your ph really low. as my solution sits it raises as well so thats whats happening in the soil.. bad business lol keep that in range! 5.8-6.4 run off should be the same as what youre putting in

 

[polishpollack]

Have you actually done pH testing on superthrive in water? On what do you base the idea that pH will drop way down when it's vitamins? Many growers notice a small drop in pH but not significant.

 

[andy s]

ive tested all the nutes ive ever used one by one so i can add them at a certain ph annd be somewhat in range. for example ive added superthrive to my bucket of water and it was trsting at 6.8 put in 4ml of superthrive and it went to 5.3

 

[andy s]

Have you actually done pH testing on superthrive in water? On what do you base the idea that pH will drop way down when it's vitamins? Many growers notice a small drop in pH but not significant.

so yes, i have and people may not notice bc their ph may be so high when they add 10 bottles of shit it brings it down lol