Earl sent in a message about my previous hydrominder problem:
Earl Weiss says: “I think the white float is sitting too low in the water. My guess is it has some water in it. Pull it out of the tank and look at it. You will be able to see if there is water in it. If there is you can unscrew the cap and empty the water, but if it has water in it it most likely has a leak and will happen again and needs to be replaced.”
He was exactly right about the float: the next day I was trying to fix the problem and noticed (top picture) that the float was full of tire cleaner. I replaced the float and I think everything is fine now. Thanks for the comment Earl and if you want you can check out the exciting video again so you can notice the problem now in retrospect.