Water change?

[Blahenazo]

so do you have 2 pumps that pump EXACTLY the same amount of water in and out of your aquarium, every time ?

And even if you should find it , what happens if 1 pump malfunctions , or it pumps slower by a bit of dirt in the pump=> so pumping slower. Even moving the output tube can already enormously affect pump volume of pumps. Even more of the relatively small aquarium pumps you would be using for something like this.
and to compensated the pumps difference you will need to adjust the timers ever so ofthen.


So yes you can do it with timers without floater but will it be reliable ? => No,