constant drip with salt water??

[Aquattro]

I see no benefit to this at all. More of a PIA if anything. If one pump stops, you get a flood. The other, you lose water that your ATO then replaces with FW. The whole benefit to doing a water change is at best minimized, or completely negated. With a 50g tank, doing a 15g water change once every three weeks is way simpler and better for the tank.