I use to have pump up's, then went to a ShurFlow and now we use soda canisters along with a small 2hp air compressor. The canisters hold the chemical and the compressor drives the chemical. You can ether pump up the canisters or use the direct air with the compressor. I like this system because the chemicals never come in contact with the pump or any moving parts.
We buy the parts from Foxx and used canisters from a company in California. Not including the compressor your cost is around $25. When the canisters are cleaned they will last for 12-24 months until the seals give. Once you use this system you will never go back to the pump-ups. Do a search we have posted on this in the past.
Just saw the post above-same idea.
David