Sure. I have an auto-aqua AWC, this one: https://www.bulkreefsupply.com/awc-auto-water-changer-plus-ato-autoaqua.html
and I put two 5 gallon tanks (these ones: https://www.amazon.com/Class-Customs-T-0500-Holding-Concession/dp/B079G3XMHR) under the couch next to the tank: one clean saltwater...