Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Vet does NOT recommend a pet Fountain because...

One of my cats would drive us crazy with wanting the water faucet on. So we decided to purchase this to give him his own fountain of water. He loved it, but because I did not change the filter every month (I would remember 6-8 weeks), he was getting sick with vomiting. So if you plan to buy this, you MUST change the filter every month and CLEAN it thoroughly every WEEK!!! Because of the need for a clean filter every month and the need to clean it weekly it was too much work so I am only giving it 1 star. We have decided to go back to the regular water bowl and run the faucet for him when he bothers us for running water to play and drink in. When we took him to the vet for the vomiting, our vet said she does not like these fountains for pets.