Problems with leaves, roots and PH jumping (wk 7 veg) (pics)

Hello all I am in week 7 of veg stage and my one plant is not growing and the leaves are changing yellowish brown on the bottom. Also the same plant seems like it's not drinking up enough water compare to my healthier plant. My ph is jumping to almost 7.7 from 5.2. I don't know what to do. I use fox farm nutes, only 1 tsp each since I have about half a gallon per plant. I am using bubbleponic hydro system with distilled water. I have 6500k cfl lights, multiple fans and 1 exhaust fan.

Recently I added some filters on the outside of the cabinent over the fans to prevent the odor from getting worse. I don't know if that is effecting anything. Also I did the sledgehammer flush for 2 hours last week to try to help the plant, I don't see any more negative results yet. My one plant has grown so much in the past two weeks and the sick plant looks stunt growth.

I have previous post with pics that show my progress from a few weeks apart. I don't know what to do. The roots look effected with algae or something bad. I need a experts help. I am a first timer with limited space that's why everything is so tight and small.

take a look please

Image 1 shows both plants, I started both of them the same time, the healthier bigger plant is Royal Haze and the sick plant on the right is white widow.


image 2 shows the healthier plant with some dead leaves on the bottom, I think it's from lack of light since it's a tight space, but I dropped a light down to see if that helps, but I hope it doesn't burn the plant.


Image 3 shows the sick plant bottom leaves turning yellow and brown, I thought it was from lack of light but it now shows some damage higher up also.


Image 4 shows the sick plant size


Image 5 shows the healthier plant size


image 6 shows the healthier plants roots


image 7 shows the sick plants roots


Lastly image 8 shows some of my light and fan setup. I have to reconfigure my lights as the plants grow but the larger plant is at half the cabinet size but I want my sick plant to grow equally before I switch light schedule to flowering stage.

The sick plant will never recover in size or yield and I am probably one of the most optimistic people (gardening wise) but I have to say that that plant wont catch up and is probably not going to make much of a harvest and at this point you MAY be wasting your time with it entirely but plants do snap back , they just don't usually amount to much. It would be literally like asking you to work out when you have the flu. If the dark colored roots on the sick plant are dark brown , black, or any grey or soft and mushy spots you need to cut those out. This will keep the water from turning crappy and should keep the p h lower and keep the rot from growing into other weak tissue near by. Too much nitrogen in too little water can do it also. white widow seems to be susceptible to too much N in my experience . Haze will be taller and straggly looking compared to the short fat white widow.,so both plants are growing at different rates to begin with. Having some High Plains Drifter as I type and my head is starting to feel like a stuffed squash so im sorry if I make no sense. hope it goes ok for you.

You don't mention temps at all, res and room temps would be nice. They are two different strains, that the growth rate difference. From the looks of the roots your a little hot 78 should be your highest temp for a res. 75 is perfect IMO. Are you running any h2o2 in your system? Air stones? Clean them girls up, most of the yellowing is lower and the plant is getting rid of the garbage, so help her out. Removing the lower branches and crap will help with air circulation. You will not loose quantity, the plant will make up for it in better locations on the plant. JAS

can anyone help me with this one? https://www.rollitup.org/marijuana-plant-problems/740876-grow-box-conditions-ph-problem.html#post9732059

I have air stones in both containers. And yes. Have some co2 buddy boost underneath everything. I clean the containers when it looks to dirty and I add water everyday to half the size of the pot. I will clean the branches off to see if that will help. The roots are not brown or black but dark green and white. I will inspect the roots better and try to get rid of the darkest ones. When should I switch to flowering stage? I heard when the plants are at half the size of the grow area? I'm 7 weeks in, is that ok or should I wait longer?

the temp varies because it's a tight spot and the cfls were to close to the thermometer. I bought a digital thermoset/humidity which will be here soon. But I see the thermometer read from 90-70 depending on the locations of the lights so I don't know the true temp.

also I just covered the containers with foil tape last week to help reflect light and also I had clear containers, I didn't know that was a no no.

5.2 ph for hydro? you should be at least 5.8, also you should be monitoring your ppm's, that's important for hydro.

The color of your roots is an indicator, green = light, brown, black = fungus soon to be rot. Black containers are best but if you can block 100% of the light you will be O.K. Flowering will be determined by your overall height. Basically plants will shoot up 25-50% once they flower. If you plants are 24" then they will finish from 30-45 inches depending on strain. Your the only one in the position to gauge this. JAS