I'm running the Rio+ 200 in my 10 gallon also doubling as my CO2 diffuser. The flow rate is fantastic for that size tank and it's fairly inexpensive ($20 I believe). Granted, I also have a tetra EX30 filter that gives my great flow for the mid-top range of the water. I have my Rio mounted in the bottom corner of the opposite side of my filter and it's amazing. It also produces very tiny bubbles of CO2 that take quite a long time to float to the top and often have time to stick to my plants. Very happy with the results.