Slow growing??????????????????

Hey guys Can I get some help please?I got 8 plants about 3 weeks old growing very slow.The problem that I have come up with is temperature.It is in the basement and has been at about 55 to 58 degrees in the room.I have went and got a climate control small forced air heater and have them on 80 degrees now.Do u think this was my problem?I have 2 Feliz 125 (8500 lumens a piece)watt hanging above with 8 100 watt cfls that were kicking ass in the summer when the basement wasnt freezing.Is 80 degrees a little hot or would 75 be better?Thank you for all your replies!

76 is what i've heard is optimal as the high and around 56 lights off is also what ive heard and works well with mine

80 is good for veg. The warmer it is, the faster they grow in veg. When it comes time to flower cut the temp back to 72-75.

Second the HID lighting, if you have the means, its a great upgrade. Once the summer hits you can route the hot air into your house or out through your furnace exhaust vent. But having those heaters at about 75 should help a lot while keeping energy costs lower. Take a good look at the little heaters, some of them can draw more than 1k watts if you have em on high.

Temperture
Marijuana can survive temperatures from 32 degrees F to over 100 degrees F. Cannabis will grow best with a temperature of 70 to 75 degrees F day and night. Higher than 90 degrees F the enzymes within the plant begin to breakdown and photosynthesis is affected. The same is true for low temperatures.


Source: http://www.greenmanspage.com/guides/indoorv1.html