I have a 40 gal AIO tank that is tall and I'm short... I've been getting on a step ladder for water changes and I am considering a submersible pump to refill the tank after my water change. My tank is new-ish, about 10 weeks, and I'm doing weekly 5 gallon changes. It's a struggle to pour the new water in without disrupting everything and making a mess, so I think this is my best bet. What do you guys recommend for this purpose? I would like something inexpensive since I'm only going to use it for a few minutes a week, and once my tank is more established it will be even less frequent. Thanks!