Seedling problems... Can anyone help??

So my seedling is a little under a week of growth. It was doing great till today when I checked on it. I opened my tent only to find this:

Can anyone help me figure out what the problem is? It's turning a dark green and won't support itself. It's in pH'd water at 5.7 in a Waterfarm drip system. I've had CFL's on the plant since it popped. Thanks.

just so u know im kinda a noob. but nobody has helped yet so here we go... is that rock wool theyre in? and if so, was it green like that when u bought it? if not u may have algae. it usually isnt a prob w full grown plants but i hear it can w youngsters. also whats yr watering schedule. they look overwatered imo. i know they say u cant overwater clay pellets, but i managed to do it w mine. ive cut back to 3 times a day for 30 min each time. no water at night. are u giving them nutes? more info would be helpful. like i said im a noob and this is my opinion. hope this helps. peace

Wool looks slimey for sure, gotta have that stuff out of the light.

man u overwatered it

Start again theyre fucked.Put a bigger gap between waterings next time, they rotted at the stem base a collapsed.

That's either algae covered rockwool or that green foam shit you stick flower arrangements in. Either one crap for starting canna seeds.