new grower nutrient lockout?

chooper93

Member
Hello, I have been growing 3 plants in a 4x4x7 grow tent and I'm running into what appears to be some sort of nutrient burn/deficiency and I'm unsure how to treat it because I'm not sure if it's nutrient burn or potassium deficiency or what. This is my first grow ever so I have absolutely no experience but I do have pretty good knowledge on the subject. I'm just looking for some help diagnosing what's going wrong with my girls. some background information they are at day 25 of flowering I'm using a 400 watt hps light as well as a vent fan and an oscillating fan. I also spray some cO2 in there every few hours not sure if it's helping but i do. Also the soil is white because the top few inches is play sand to keep fungus gnats under control. Another sidenote I started them under cfls for the first 4 weeks and due to not understanding my light timer they got a 23/1 light schedule rather than 18/6 as I intended. For nute's I'm simply following the directions of a starter kit and there's been no big change in nutes other than a slight increase in volume of watering ,not concentration of the solution. Please help this is my first major problem I don't know how to handle. I usually water every other day with a gallon of nutrient solution with biothrive bloom 10 ml, cal mg 5 ml, biothrive bud 2.5 ml, biothrive marine 8 ml, and 5ml of fishshit(literally the name sorry). I'm thinking it's either nutrient lockout or a potassium or magnesium deficiency. I'm thinking of switching to a water feed water feed schedule and seeing if that helps, but any advice would be appreciated.
 

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DaleW

Well-Known Member
If youre at 25 days that is just about close to 4 weeks, the time when the plant really demands potassium as flowering is kicking into gear. There is a good chance that it is potassium deficiency. I had the problem myself and pk/13 fixed the problem.

Also just a suggestion, instead foliar spraying liquid co2, youre better off just mixing a good nutrient light foliar spray solution. ph it to about 5.7 and spray em 2 to 3 times a day. Youll get better results. I wouldn't suggest covering the soil with sand unless youre using fabric pots. Gotta allow air to flow down there for the best results plus, it is more comfortable to the plant. Feed every other watering, not every watering.
 

polishpollack

Well-Known Member
From your nutrients and the light green appearance, it really looks like the plant isn't getting enough nitrogen.
 

chooper93

Member
If youre at 25 days that is just about close to 4 weeks, the time when the plant really demands potassium as flowering is kicking into gear. There is a good chance that it is potassium deficiency. I had the problem myself and pk/13 fixed the problem.

Also just a suggestion, instead foliar spraying liquid co2, youre better off just mixing a good nutrient light foliar spray solution. ph it to about 5.7 and spray em 2 to 3 times a day. Youll get better results. I wouldn't suggest covering the soil with sand unless youre using fabric pots. Gotta allow air to flow down there for the best results plus, it is more comfortable to the plant. Feed every other watering, not every watering.
awesome thank you for the feedback, I suspected it might be potassium but I didn't want to make the wrong call and hurt it more. could it be possible that the potassium deficiency is from salt build up? as I don't usually water till runoff occurs. I was thinking of flushing them out before continuing on as you say.
 

chooper93

Member
From your nutrients and the light green appearance, it really looks like the plant isn't getting enough nitrogen.
thanks for the reply. I thought so too at first but I think it's displaying different signs because of the flowering stage and the middle of the plant localization of the discoloration
 

polishpollack

Well-Known Member
Read the contents of each container. If potassium is in at least one, then it's kind of unlikely to be a potassium def. I've looked up fishshit and it doesn't appear to have an NPK ratio. It just has bacteria to help with nutrient breakdown. Is there NPK on the container? Right now, it doesn't look like you're giving much nitrogen. hmm, usually plants pull nitrogen from bottom leaves and move it towards the top. if you're yellowing in the middle, I have no idea what causes that so all I can say is good luck to you. maybe it is potassium.
 

DaleW

Well-Known Member
awesome thank you for the feedback, I suspected it might be potassium but I didn't want to make the wrong call and hurt it more. could it be possible that the potassium deficiency is from salt build up? as I don't usually water till runoff occurs. I was thinking of flushing them out before continuing on as you say.
Well because you were feeding every watering, yes a flush would be ideal. You still want to try and feed them some potassium between that 4 to 5 week window if you can. I know that someone said that if there is potassium already added in one of your nutrient solutions you are find however in my experience i had to use a standalone supplement. Just my experience though.
 

chooper93

Member
yea i flushed them out and they are coming back strong but now one of the three is displaying alot of slight deficiencies I'm gonna give them a 3/4 feed because I flushed them out a 3 days ago and watered yesterday so i'm thinking nutrients are flowing they're just hungry, I'm hoping haha
 

OldMedUser

Well-Known Member
That plant's hungry and those leaves are fading as the tops are stealing from them.

Good feed of everything will do it.
 
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