I used to put rice cereal in Heather's bottle, but we had a lot of trouble with the nipple getting clogged, even after trying to enlarge it..... so, then we started mixing cereal with formula & feeding it to her with a spoon. She really seems to like it. One of the moderators told me that I might be able to get her to drink more if I cut back on her solids, so I'm only giving her one bowl of cereal each day.
We've been working on the 4 hour EASY with Heather for a couple of days now. She only drank 13 ounces all day yesterday (including the cereal). Today, though, she's already had 9 ounces so far.....
Also, Kezia, wrote that there's a thicker formula that you can buy, that has rice in it already. I'm in the US and have found that Enfamil sellls one called A.R., which I'm going to try.
Good luck!