Not Enough Light?

I have 3 mother plants approaching 30", and I fear my current lighting is becoming insufficient.
I have a 4' fluorescent fixture with 4 32 watt T8 6500K tubes.
My plants have been starting to appear as if they've been heat stressed or nute burned, but they're growing in Happy Frog potting mix without any nutes so far, and the temp is under control.
Please Help!

pics?
moe light ALWAYS helps (except for seedlings and clonelings)

Sorry, not available camera.
I know more lights is always good, but what I really need to know is, what happens when there's simply not enough light?

pics please

ur plant will grow very slowly, struggle to produce good shoots and yield low

OK! So after some finagling, I got these pics. Do they shine any light on the situation?? lol... puns are the best.

looks like its lacking something check this site out , hope it can help you http://www.420magazine.com/forums/problems-pests-disease-control/81275-cannabis-plant-pest-problem-solver-pictorial.html

U can definitely tell from pic4 that there isnt much light getting to the bottom half, probably due to a lack of reflective surfaces, but being inexperienced, I wouldn't know how serious the problem is yet.

EDIT: From the 420mag article, it looks like possible potassium deficiency.. but still not convinced. Has anyone here had experience with this?

Some heavy LST or scrog methods would be preferable with that lighting. You likely have a foot and a half away from the bulbs of good lighting. After about 2' most of it will struggle.

To increase your lighting you could get something reflective to partition off that open area "bamboo room divider and tape some panda film on it, piece of cardboard/panda film or something", you're losing a lot of light, it only needs to be as high as you want to bring the light. Maybe also something more reflective for the walls, flat white paint or panda film. Push them back more toward the wall. Basically make it a smaller area so the light is confined to a smaller area.

What, if any, would be the alternatives to the training options? I am very inexperienced and these practices frighten the shit out of me.

Also, shouldn't these methods be applied a little earlier in the vegging process?

It's too late for scrog. But training is pretty simple. Yours might be a little bit more difficult because of their size. The new growth is the easiest to train as it bends more easily. You can normally bend that close to 90 degrees without much stress. Once the stem has hardened it become more difficult. Just be gentle and start off only bending the soft parts "the tops". And avoid going more then 90 degrees to start.
Edit: Option to training would be more lighting, and training can be done at anytime. After about 4 weeks into flower I find it more difficult as the stems even on the tops have started to harden.

i agree smaller area.go to home depot and look around.

why not add a couple cfl's for side lighting?

Thats exactly what I was thinking about! Gonna have to get more CFLs, I've got new clones under the ones I have.

Ideally, yes, by topping, fim, lst or scrog. In this case you might want to tie down the main stem ( don't want to break it, just tie vertically) long as it's level with or below level of any lower branching, that should encourage bushiness. I used to have a similar setup, I laid a flourescent on top of the pots with tube up, helped fill in those areas that were far from the light.