Although this hotel is very close to the Osaka Aquarium, I don't think I would recommend going here if you're planning to do more things elsewhere. If you want to do anything else, you have to ride the metro for almost 10 minutes to and from the hotel, which gets tiring after a few days, and the whole hotel is on the third floor with no elevator and steep stairs, so getting the luggage up and down was a chore.
Other than the location, it was an okay experience, the room looked nice, and seemed mostly clean, but don't expect a nice view from the hotel.
The ac in our room had however not been cleaned in a long time, and was making weird noises.
Be prepared for the size of the room, and the shallow fridge. Both left us wanting a bigger hotel room considering we had big suitcases.