Should I worry about these yellow tips on my leaves?

Hi, I've been noticing some leaves dying near the top of my plant lately. They've been on 12/12 for almost 3 weeks now and I just pulled 4 males for showing heaps of balls but none of these plants seem to be showing sex yet, so I'm hoping females. I've just been watering them every two days (water until it starts dripping out of the bottom of the pot). Do you think it's time to start adding nutes? Is the leaf burn a sign of lacking in something - can anybody identify from these pics? I don't think it's heat from CFLs burning them because the bulbs are not anywhere near touching the discolored leaves...The close up photos are of the plant on the far right in the big photo. Thanks a lot!

Also is it worth cooking up the males in some butter and eating it? They've had their balls out for about 5 days now...

it looks like nute burn u havent been useing nutes right wat kinda soil mate and have u checked ur ph it could be nute burn phosphorus deficiency or Potassium deficiency

jaydiesle said:

it looks like nute burn u havent been useing nutes right wat kinda soil mate and have u checked ur ph it could be nute burn phosphorus deficiency or Potassium deficiency

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Yeah, the soil I'm using says it has organic time release fertilizer, enough to power a plant for three months. Sorry, should have mentioned that at first. I can't check my PH at the moment. Is it looking more like too much nutrient, rather than too little? I've got some blood and bone stuff I could add. Thanks.

id space out the lights a lil better maybe 4 on top 4 spaced out in the middle and if you want id use reflectors on the top lights since your setup looks homemade you can use the disposable turkey pans or the pie tins as cheap easy reflectors just a suggestion

growingnewbie89 said:

id space out the lights a lil better maybe 4 on top 4 spaced out in the middle and if you want id use reflectors on the top lights since your setup looks homemade you can use the disposable turkey pans or the pie tins as cheap easy reflectors just a suggestion

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2 of the plants are too tall and I can't fit any lights above them. The enclosure is very small and wallpapered in reflective card and mylar (the walls are movable so I keep the plants surrounded by reflective walls). What would be the point in putting reflectors around the bulbs? Is it bad to not have lights on the top as well?

well thats not good eithar if theyre already that tall have you begun flowering yet cause when that happens they double in height but thats not going to go well if your already out of space and yeah im pretty sure thats the best way to give them light but like i said that wont matter if you cant increase the height of your setup she looks pretty good though nice and bushy

can u take a pic thats a lil clearer if its nute burn and it gets a lil worst just flush than for next watering give them 1/4 strength nutes so u wont get any othere deficiency they dnt look to bad and try and get a ph tester u needa know ur ph mate

contributor said:

Also is it worth cooking up the males in some butter and eating it? They've had their balls out for about 5 days now...

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No throw away the males, its not a good habit to get into 'eating male's balls'. I agree give it a flush ,no nutes for a week then reduce by 20% should be enough.