@Paul B has an awesome DIY baby brine shrimp feeder design. It's in his book and it's been mentioned on here. I think saltwatersmarts has some articles on that and the brine shrimp hatchery.
As far as the correct method to feed rotifers? Let's consider this post a bump. :)
Ok and I use a coffee filter to catch the rotifers and when I add the filter to clean water, there is a little bit of rotifers. However when I collect the water that goes through the coffee filter, there are more rotifers in that cup. Would it be OK to add them to my fry tank if I mix them with clean water?