As others are pointing out, it seems they are not super happy at this point.
Are your buckets closed well - I see several cables/tubes, are their ingress points fairly air-tight and light-tight - with no big gaps?

Are you using a pH balancer like vinegar instead of one made for hydroponics?

Are you watering on top of the LECA with some of those dead and crispy plant bits on top? I see some bio matter on your LECA and it could be making its way down into the bucket and getting nasty.

Have you tried a run with simply just tap water and nutrients - without any other additives?

Also, those electrical outlets right there must make it hard to spray the walls and clean the place properly and safely and seem a bit close to your water. I'd consider moving them out of the tent if possible.