check the maximum pump height
 

Just a reminder. When looking for a pump make sure you check the maximum pump head (how high can it pump). Some pumps might not be able to fill your pots. I bought a small (120 gph or so) pump and it was pretty useless for the 11 plant system. It does work on another ebb and flow system I have (because of about a one foot difference in max height).
CM

It is always better to buy the biggest pump you can afford and use a flow control valve to adjust the GPH to your garden. Then if you enlarge your garden you just open up the valve or redirect some of the flow to add oxygen to your reservoir.