Its mylar not aluminum foilIt just looks overwatered to me. Yes, take the aluminum off from beneath. Your plants need more oxygen at the roots. Also, if soil is damp, aerate. You can save it. Oops, just noticed this was bubblebonics. Maybe you have overferitilized? Definitely take the aluminum off.
that's prolly what it is, make sure you're not watering it too much.I would take the aluminum or mylar out from underneath of the the plants where its covering the soil.
Its a bubbler system not soilthat's prolly what it is, make sure you're not watering it too much.