Here is a link with some pics to my ballast install in my 210 on planetnautique. Do a search on that site, there are a bunch of good installs on 210's.
Yea i have a 11/2 bras ball valve connected directly to the brass thru hull fitting. 11/2 pvc pipe out of the thruhull to the pumps. I can turn on all three pumps at one time. Each pump is rated at 10gpm @ 0 psi. More realisticly i am getting 7-8gpm with friction through tubing and elevation. I fill about 1000-1200lbs in ~ 7-10mins. My boat doesn't do well with a lot of weight the wake gets to washy. Personally i don't even notice the fill time by the time i back the boat in the water and my buddy parking the truck the sacks are full.
4 out of the 5 pumps work first time but one pump doesn't always fill right away. I will be checking into it this spring to see what the deal is but I have always just delt with it filling it on and off a couple times then it works.