Seedling leaves turning brown! Please Help :(

This is my second grow, and the problem is the same as my last one. Last time i thought that the soil was a problem, i changed the soil but the problem for this growth is the same... now i think the water ph isn't ok since i dont have a ph meter... Please help me to determine the problem and to solve it please

id say its a burn or mold damage, flush it for now and you might have to transplant to some less nutrient abundant soil. i prefer popping seeds in rockwool because it stays moist in a dome and it doesnt have any nutes(but i do soak them in rainwater for minerals).

looks like light damage...whats that little thing under for lighting?

Yeah before true troubleshooting can begin you have to know all the variables, and when talking of MJ the Ph is a huge deal...just get the solution to check with and then check your run off...it is cheap and easy to use, and is accurate enough...I wouldn't buy a meter unless I could afford a really good (and expensive one)...because seems to me that a lot of the cheap ones just aren't reliable. The solution is easy to find, cheap to buy and accurate as long as you aren't color blind.

it's under 130w 6500k cfls for now 24/0... plant's not too close to the lights
i flushed it with a bottled water and will see how it goes...

I had this happen on one leaf in one spot from a single drop of water under 100w cfl. The water drop worked like a magnifying glass and burned that one spot of the leaf, however I keep my cfl's about three inches away. I now make sure there aren't any large drops of water that stay on the leafs.

Yah this just happened to one of my bag seed; I'm using it as a buffer to stop anything from happening to the god bud lol

Too much light is my guess as well.

You soil looks like crap, seriously.
You need MUCH less watering and I would use different soil brand.

if youre worried about the ph of your water get a gallon jug and fill it with tap water and let it sit out open for about three or four days or longer and then it wont have the chlorine in it anymore and if you have a good water company you should have neutral pH water