Backyard Aquaponics
A place to discuss aquaponics

Can anyone tell me whats wrong with the lettuce? Is this bacterial disease or foliage burn?

Bacterial or viral... Though viral's a bit of a dirty word now a days..

I'll go with bacterial leaf spot. Bacteria thrive in moist environments so try to keep water off the leaves (from splashing, condensation... whatever) and increase the air circulation.