Lease alteration clauses are broader than renters think, and an unapproved install can become the landlord's property with restoration billed to you.
Ask about the attachment, not the device. The four things a landlord is actually worried about, answered before they raise them, plus what to write.
Adhesive hooks hold about 7.5 lb. A two-gallon pet fountain is heavier than that before you add the housing. The arithmetic no mounting guide does.
Mid-term, generally not. At renewal, generally yes. The exposure is not who owns the building, it is the date your term ends, and what to do first.
A silent lease generally is not a prohibition, and courts in most states read it that way. It is still not permission, and here is why to ask anyway.