My betta strawberry has sbd, and went from floating to sinking so i've moved him to a 1/2 gallon tank and filled it with greenwater from my 29 gallon tank, do u think that would help at all?

Sorry dont know much about Bettas.But the green tank should have very good water. Test to make sure. My Ranchu gets SBD when there are to many Nitrates and Nitrites in the water.

tested the greenwater awhile ago and params were good

I hope this helps your Betta

thanks, i hope so too, i really dont wanna have to euthanize him