Also after reading DrThompson's post on automatic water change I was determined to setup something similar for my own tank. I saw the use of the stenner pump as well as the litermeter in use. Spoke with Dave about his experience with the stenner pump and initially decided to go this route. I found a used dual head stenner in great condition and jumped on it. After some more reading I decided to try out the new Neptune DOS instead and ordered one for black friday (which would not arrive until a few weeks ago). I think the stenner would have been fine but I am a gear junky and I really like the integration with the DOS and apex fusion. Now that the DOS is setup I will probably just resell the stenner pump.
I setup a 90 gal container to hold mixed salt water in the coat closet not to far from my tank. I ran an RO line to it with a float to fill it whenever it gets depleted. I plumbed a Mag pump to mix the water and circulate it daily ( powered by an EB4 through the apex ). Unfortunately I dont have room for 2 containers - therefore I must shut down the auto water change when the reservoir runs low - turn on the RO line - mix salt - then restart the awc system. I initially tried red sea salt which seemed to work well but am going to try HW marine mix Reefer salt (was on sale during Christmas time) next.
Here is a photo of the closet with the container and a few shelves i cut to fit around it.
And the DOS pump installed above the container
Seems to work well
Only a few hiccups - it took a long time to prime the lines to do a calibration test (it primes/manual doses at a slow speed)
And the fusion setup for water change has one pump run backwards to pull water out from sump so I had to reverse the lines on the second pump. One pump adds new water while the other draws it out and dumps it into my drain (similar to Dave's setup THANKS DAVE!). I will have to call neptune to ask how I am supposed to periodically run calibrate (its easy to run) with the line that pulls water out reversed. I may install a Y-Valve in the line to make calibration checks easier.
As for the tubing through the attic - i ran PEX line which is supposedly a oittle more durable than standard PE tubing. Next time I am in the attic I might take a photo to document the installation which I tied to the tops of my trusses for a clean unobstructed install. If you have seen my prior photos, you wouod see that I really love a clean organized installation when it comes to cables/wiring/tubing .
Thanks for checking in , I will try to post a bit more in the near future...