Curling down leaves

The setup: 3 plants I am using 200w envirolites (veg), using tap water every other day. The lights are about 4cm away from the plants. The plants have been under the light since 20th feb. I have transplanted it once. The nutrients I have been using Plagron Alga grow once a week. Started using nutes 2 weeks ago The soil, miracle grow (only soil I could get) Looking to flower asap.

The problem: The leafs on all the plants are curling down + maybe a little dry. The lower set of leaves have started going a little yellow (only on one plant). Also should I be considering transplanting before I move to flowering? Any remedies will be greatly received. The cheaper the better. Thanks

Its hard to tell with so few details and pics it could be:
Overwatering
Overwatering drowns the plant by stopping the roots getting much needed oxygen. Make sure the plant pot feels alot lighter let the top soil dry a little then water. Look into hydrogen peroxide.
Soil
I have found that useing shit soil kills plants. The soil your using has time release nutrients which means it burns roots that could be the yellowing. The plant is trying to tell you its deficient of nutrients because the time release nutrients block uptake of the real nutes your trying to feed the plants. Buy bio bizz plagron ect please I had to bin 5 plants my first go by making this mistake.
Nutrients
Always use half the recomended fertilizer full strength is almost always to strong especialy considering your using only 200w envirolite. thats about all I can give considering I don't know strain and minor details I hope you do well PM me with all details if this doesn't work thanks.

More info: Been using light sch 24/0, The strain is euforia dutch passion, each of plants have five sets of leaves. They are in small med sized pots and the problem has occured in the last five days. Growing in a small setup. Don't have a digi cam available at mo. So no pics.

Ross....great post! I'll only add one more guess because no photos.....possibly rootbound?

PS....stop adding nutes, check water and soil runoff ph.

Revised: The Complete Guide To Sick Plants,pH and Pest Troubles - PlanetGanja.com

Here is a great troubleshooting link.

Good luck.

Don't forget underwatering also.

It can cause droopy leaves, dying leaves.. basically the exact same symptoms of over watering.

Maybe it's too cold for the roots...put something under the pot, so it is not exposed to the cold floor...
Are your roomtemps ok??

zeubulon, during the day have the door open for air circ/vent during the day. At night close the day so the temp flucates during day/night. The plants r placed on glass. from weedhound posts I think it could be rootbound? Are these the symptoms? This is my first grow have put a lot of time/effort watching these babies develop

might also want to see how much nitrogen your given them
check the back of the nutes u have use and the dirt and that will tell ur there nitrogen content

the reason i say nitrogen is because thats what alot of plants are suffering from when just the bottom leaves start turning yellow
thats is the main problem i ever have with mine is nitrogen deficient

but the curling ross probably hit it on the head with the over watering

post up some pics and ur ph lvl when u get a chance