Outback LS ballast install

Guys,

I scoured the internet for countless hours trying to find a solid plan to plumb the stock ballast tank in my new to me 03 Outback LS. There is not very much out there about putting ballast in a DD, for the obvious reasons, but oh well. So, this is to help anybody out that may have the same issue.

1. What type of pump to use and where to mount it.

This was my main issue I was having when trying to build my system in my head. I went for the reversible pump since it is less wiring and to me just seems better quality. Since I went with this pump I obviously wanted to mount it somewhere dry AND somewhere close to the tank so that I don't use a lot of hose. My first idea was in the trunk. I don't use the entire thing at once so why couldn't it sit to the side? I then had thoughts that maybe the hose wouldn't fit between the gas tank and the water tank. These thoughts led me to come up with a couple of other places. It could be mounted in the bilge area up in front of the motor or under the front seats on the back of the dash panel. I ended up going with the trunk and everything did work out.

TLDR: the revesible pump will mount in the trunk and 1" hose will fit between the gas tank and the water tank to allow a clean looking install.

2. How much hose will I need?

If you are going to install in the trunk 20' was good enough for me to get to the tank and one to the thru hull fitting. If you decide that isn't a good spot for you then you will need to measure out the distance that you want to mount it from the tank and double that figure then add a couple more feet. It will never hurt to have extra hose.

Some other interesting facts: the inlets on the stock under seat ballast tank are 3/4" and there are 3 of them (2 on top and 1 on bottom)