ballast basics

[BP420]

Could someone go over the basics of setting up an auto ballast system? or give me link to somewhere that does.
What are my all pump options? what are the differences between them?
Is there any way to avoid drilling through the hull?
I would be ok with sticking a hose over the side of the boat and flipping my switches if thats possible.
I want to fill 2 bags, one in the bow and one in the ski locker and I would like to be able to move slowly while filling. I only have a searay with a 3.0 mercruiser so I cant load it down too much.

also I would be interested to know if there is a cheaper way to make a non auto style pump that you just throw over.
Thanks

[Iman]

Seems to me that you are practically already describing what you want to build and just need to rig up the parts to make it work.

I also did not want to drill through my hull and wanted to go cheap so I rigged up a similar system. In your case I'd probably go to Walmart and buy the biggest/fastest bilge pump they have (1200gph?) and two aerator pumps (750gph). Rig the big pump to fill both sacs and the an aerator pump in each sac to empty. The easiest way to power the pumps is just attach them to a plug that you can plug into your cigarette lighter outlet.

Aerator pumps can just be slid into the sac outlet and then clamped to stop leaks. To plug your inlet hose into the sac you'll need a fitting will connect to your pipe and also into the sac, if you use 1" bilge line from your big pump then a 1'bib to 3/4" threaded fitting will do it. You can get all the fittings you'll need at Home Depot or a West Marine type store. I ran the empty lines out my bilge line but that gets trickier since you'll have to put in some directional fittings or else your boat bilge will go to your sacs or your sac will go into the bilge of your boat.

Good luck.