In my experience it is probably game over for the bass. No way to remove toxin so if it got enough it will start doing the death roll soon. Sorry for your loss, but it happens with rays especially in cramped quarters. I have lost a 18 inch tig, a 17 inch broko, and a 24 inch royal clown knife. The tig lasted 3.5 weeks but had obvious neurological damage from it. The other two about 18 hours at most.
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