Did your vet indicate why he though the potassium dropped? You're doing everything possible for sweet Max. Wish I had any clue how to help and a magic wand.His potassium dropped to 3.3 from the 4's so even my vet agreed with that one.
Long term prognosis is not good unless his creatinine can somehow come down. No idea how to do that.
Urinating a lot can rob the body of potassium. Kidney disease causes large amounts of urination. So ear Max has been eating well so not his cause of low potassium.BTW, Doodles cardiologist told me low potassium is caused primarily from not eating enough. Not sure if it's true or not but it was a concern of mine with the large dose of Lasik since it's a potassium robbing drug.