Having problems with my sativa plants!

I ordered white widow seeds (10) they came in 2 packs of 5. 5 of the seeds are sativa plants the other 5 turned out to be some kind of indica plant... Im just going with it at this point. They are about 5-6 weeks veg and the sativa plants just arent looking nearly as good as the indica plants. The leaves are starting to yellow from the top and curling a little bit. I raised the light and cooled down the room. I have tried giving them a boost of N. They arent dying but im not happy with how they look. Any advice would be great. Thanks

you have to give us more info... what soil, whats the temp, what kind of light?...., soil ph, and nutes. could be anything with the amount of info you gave

4 to 1 soil to perilite mix. Ph is right around 6.8-6.9. The temp in direct light stays around 88 and the light is 1000wt mh. The soil i got had gnats. i have been battling with thoes since i started. I am using gognats. Would the gnats be causing the problem? I have tried reading tons of forums on gnats and i cant seem to find a real solution to the problem!

lol there ya go.. ok first of all the temp is a little too high but i dont think that is the whole problem. im on my 3rd grow right now (1st legit one) and everything is perfect and im into my 4th week of flower. My first grow i had the gnat problem. didnt reall ything it would do too much. WRONG. killed my entire plant a week before i was supposed to harvest. i have completely gotten this problem under control. im not a genius with soil but i just use straight FFOF with no perlite and my shit does fine...

As for fungus gnats... i hope ur dechlorinating your water by leaving it sit for 24 hours before feeding your plants. When you fill up ur bucket (or whatever it is u use to store water) u need to put 1/4 mosquito dunk or a little less per gallon of water. this will kill the larvae. pick those up at home depot. Secondly u need to get monterey garden insect spray. it contains spinosad which will kill the adult gnats and not harm ur plants at all. 3rd, (this is really not necessary but i just started doing it because some experts swear by it) get some diametceous earth and spread it on top of ur soil. when the fuckers crawl through the top it cuts em up like little razor blades. and also get some sticky traps to monitor the problem. i hate those things man and they will kill your plant

it may also be too late

Thanks i really appreciate it! I used MG organic and i will NEVER use it again. I have well water to no chlorine problems for me. Im on my way to home depot now! Ill keep you posted. How long did it take for the plants to recover? They just started looking bad a day or 2 ago so im hoping we can save them. Any idea why the sativa and indica are affected so differently? Is that common?

really dont know why that would be.... when this happened to me my plant died and i just started all over from scratch making sure i started watering with the mosquito dunks from the beginning. ever since ive been good and i can actually see the little larave dead in the bottom of my draining pan so i know its working. ive only been growing for 6 months now so it definitely could be something else or a combination of two things. you are definitely wanna get the gnats under control tho. btw the monterey insect spray (make sure its the one with spinosad) and the diametecous earth you may need to get online. amazon ftw

I went with an Azamax drench. The mosquito dunks arent sold here and the plant strore said the Azamax works really well. Im nervous about it. Has anyone else done a full drench? I did 1 pint of solution per 1 gallon of medium.