Gel on my roots

When I transfered my clones to the flower room in my NFT system A gel like substance appeared on the roots. Its semi clear but I have never noticed this before. Anyone know what this is?

You are getting root rot. Block all light to root zone and the res. Keep the res temp under 70 degrees and keep it aerated. You may want to dose with 35% H2O2 at 5 ml a gallon, then use Hygrozyme per instructions and you should be fine.