That might work if no corals because you don't need to replace trace elements.What if you don’t change the water and just dump it back in? I’ve seen videos where they use a siphon and run it back through the filter sock in their sump therefore just filtering the water. Many people run their tanks without water changes and this way you can still siphon your sand bed without storing salt water.
I’ve been debating which method to try once my tank is established: a) weekly 5-10% water changes with Brightwell Aquatics Neomarine salt and dose 2 part or b) no water changes and dose with something like Tropic Marin’s All-For-Reef single solution that doses all major and minor trace elements which might be a little more expensive.This seems like easy way to remove nutrients from the tank without changing water. Like wise if you just ran the line to a filter sock in a sump or just hanging in your tank would also work.
@Jamie S Trace elements are an entire conversation and then some haha. There are many successful tanks that rely only on water changes for trace elements. From softies to sps tanks. I think this is purely dependent on just how much is consumed in your tank and how big and frequent those water changes are. The only sure fired way to know would be to to send a sample of your water for an ICP right after a water change and see. Then you have actual numbers to see if this would keeps everything where you want it. One could know more also submitting a pre-water change sample to see just how much things changed with that water change.
That being said though, I think most people who rely on water changes alone just see consistent growth and good/acceptable color and see no reason to dose.