im using it to dose kalk out of a 5 gallon bucket in cunjunction with a top off switch. works perfect never too much at once. Hasn't stopped working after 2 months of constant kalk water through it. I have had to replace my tubing but the pump still pumps

I use one of these to draw the air out of a 4 inch aqua bridge that is 8 feet long and sits 18" above tank surfaces. This amazing little pump sucks every bit of air thereby by lifting the water to fill it completely. That blew me away for an item that is only $15. I bought 2 more for future projects :) PS: Buy the filter to prevent clogs, they should be used with any vacuum pump. You can make your own if your handy, not much to a filter can.

Excellent product for external overflow use and works perfect for top-off in conjunction with micro valve by two little fishes to control the flow. I put it to a timer to top-off my sump.

works great, recommend getting the optional filter to protect pump. works good as a dosser pump also.