Plants leaves are yellowing, just entered 600w HPS

Hello!
This is my first grow, my friend set me up with these plants who also grows, his plants are beautiful (Huge heads, aerating pots and massive yields)
I vegged them for about 3 weeks (Which is all they needed as they were given to me as babies anyway) where most of them were fine and perfectly green and happy, under CFL/Fluorescent lights.
I then moved them to the HPS 600W grow area/room, where a 12/12 light is happily set up along with a carbon filter for smell and constant new air is being given to the plants.
After a week, the most of the plants started to yellow on the leaves, one of them is looking very bad.
Apologies for the photos, unfortunately the light is very bright and overwhelming for the camera, but I did the best I could. (Next time I will take the pictures when the light is off and use a flash or something)
I'm sticking to the schedule that my friend gave me with the feeding, doing it the same way as him and he doesn't have this problem.
What is it that's doing this? The soil is the same soil that my friend uses too.
However, it's cold here in the UK at the moment, and when the lights switch off later on, it may be getting a little chilly in the room, I'm not sure if that could play a part in the yellowing of the leaves?
What causes yellowing of leaves at THIS stage of the plant? It's a few weeks after vegging, but not flowering yet, just in the middle.

What nutes you useing. how much

Root accelerator ,bio grow, bloom and top max , 1 ml per litre per litre of bio grow per day, 3ml per litre of bio bloom per day and 1 ml per litre of topmax per litre every day, but I gave them just water for 2 days to see if it would improve anything and nothing has changed

jaygrowster said:

What nutes you useing. how much

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Root accelerator ,bio grow, bloom and top max , 1 ml per litre per litre of bio grow per day, 3ml per litre of bio bloom per day and 1 ml per litre of topmax per litre every day, but I gave them just water for 2 days to see if it would improve anything and nothing has changed

When you water you want to water ntil you s getting run off. Theres no way you should have to water or feed every day.
I see starving
Heat issues
watering
And with the way you have been watering prob gonna run into other issues such as salt buildup, lockout.

themikey420 said:

Root accelerator ,bio grow, bloom and top max , 1 ml per litre per litre of bio grow per day, 3ml per litre of bio bloom per day and 1 ml per litre of topmax per litre every day, but I gave them just water for 2 days to see if it would improve anything and nothing has changed

Click to expand...

Way to much nutes .. your feeding because heat is making pots feel light you need to pot up to bigger pots bro.. to muxh going on in them pots .

What stage of flowering you in.. I use bizz nutes my self there bril . Just Gota now how to use them brah..

Need to no what stage flowering you in to give you some good advice..

Slow down on the watering seriously. No way your freind waters this much and has healthy plants.

I use biobizz also and use roughly the same mix as you in similar size pot and i only water once every four days with 1.5 litres of solution per plant.
You gota let the soil dry out a little before watering again. Look i to getting a moisture probe. They about a fiver in b&q and it doubles as a ph meter aswell.

Personally i would give them a massive flush then leave them about 5-7 days then resume with a watering schedule like i described above. But dial in your own each grow is different.

You should not be feeding bloom nutes till you see flowers starting just after the stretch. Maybe a lil shot of (n) bio grow 1 ml per ltr all the way till last week . Flowering stage start of with 1ml per ltr for 2 to 4 feeds see how your girls react then up to 2ml per ltr for 2 to 3 feeds . If your girls are liking the nutes up ,the dose to 3 to 3.5 ml per ltr

littlewing said:

Slow down on the watering seriously. No way your freind waters this much and has healthy plants.

I use biobizz also and use roughly the same mix as you in similar size pot and i only water once every four days with 1.5 litres of solution per plant.
You gota let the soil dry out a little before watering again. Look i to getting a moisture probe. They about a fiver in b&q and it doubles as a ph meter aswell.

Personally i would give them a massive flush then leave them about 5-7 days then resume with a watering schedule like i described above. But dial in your own each grow is different.

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Massive flush no just cause loads of problems.. organic don't ever flush, you Fuk up the microherdes and all the bacteria .. with in the soil.. drop nutes completely yes .. flush no just water till 10% run off

Maybe so but. Feeding that much i that short time the salt build up will start locking out nutes eventually. I think in this case a flush would help to remove some leftover nutes and breakdown some of the buildup.

As for not using bloom til flowers appear i disagree. I use small amounts of bloom toward end of veg with bio bizz. The bio grow has no trace minerals in ther and without using more micro-nutrients it gives a way of getting these elements into the soil without buying more expensive micro nutes.

I dnt start using top-max till i see flowers. Then i start off slow.

But one thing we can agree on is this feeding and watering schedule needs stretching out some.

jaygrowster said:

Massive flush no just cause loads of problems.. organic don't ever flush, you Fuk up the microherdes and all the bacteria .. with in the soil.. drop nutes completely yes .. flush no just water till 10% run off

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I am not gonna flush because the soil is way to damp anyway, I think I need to let it rest and settle with the water its got, and kush4us said it needed flushing which is completely wrong in my opinion. im giving it too much water anyway and there's not enough heat at the moment in the night, the way my friend gets away with watering so much is a constant warm room, so that it dries up quickly.
Unfortunately since its my first grow I can't insulate the room as much as I would like to, so I think I just need to slow down on the nutes and water, would you guys agree?

That is one thing we can all agree on..
I think evan with a warm room its too much watering.

Good luck man.