The dialyseas sucks water from the sump and runs it through a dialysis membrane and returns it to the sump. The water that returns has almost everything removed from it during this process. The specific gravity of the water returned is about 1.004. There is a conductivity meter that monitors the salinity. Eventually the specific gravity falls as more water is dialysized through the day. I presently have it set for 7 gal a day. When it falls below a threshold I have set, (1.025) a pump in the dialyseas pumps concentrated brine into the sump ( little by little) until the specific gravity is where it should be.
The result is that there is very little change in the salinity even though I am changing water all the time. It works quite well. The unit also produces 75 gal a day of RO/DI water. Although the dialyseas is capable of replacing evaporated water, I don't use this feature. I have a litremeter that pulls the water through a aquamedic kalkstirrer and adds it to the sump.
Here is a pic of the inside of the sump. You can see my carbon and GFO reactor, along with my protein skimmer.
