You need to let the skimmer break in. This takes 3 or 4 days and it needs to break in , in the main tank. I dought the bubbles had anything to do with the fish but MB the added
O2 (though its the wrong type of
o2) made the fish happy from added
O2 , or the added flow kicked up ammonia causeing stress.
Then whene it overflowed it means its breaking in. Just set the bubble level real low and adjust a few times a day as needed.
Debris being kicked up could be from a few sources. To much uneatin food , or fish waste or other debris collecting and the added water movement is kicking it up. A
HOB media filter will help with this along with good water flow and proper feeding habits.
Its best to feed more often and in smaller amounts with 4 or 5 types of food.
You could use a turkey baster type device and right before water change blow small areas of
LR and sand. Then the water change will help remove more along with the Hang On Back media filter and feeding scedule.
Also readjusting your CUC will help. Nass snails and hermits would help.