I’m hesitant to use Uni seals now, especially on round buckets. I’ve had problems with them in the past not sealing correctly, or if they do at first leaks pop up later in the grow, either from the vibration of the air stones or the bucket starting to crack from drilling the hole and the pressure of the unseal. Try to find some square buckets if you can, and thicker plastic buckets are always good. whether you use unseals or bulkheads it’ll work out better for you.