# How much flow



## kellymm (Jan 30, 2010)

How much flow should i have in a 20g high planted tank


----------



## Six (May 29, 2006)

Are you planning to get a fish that needs a lot of oxygen? I guess I'm not sure why flow is that important. A filter for a 20g should be adequate unless you're selecting an oddball fish that needs higher oxygen. 
If you're keeping plants, you don't really want a lot of flow because that dissipates the carbon dioxide that the plants use to grow. If you have a plant tank, flow isn't really all that important. 

GL.


----------



## Diana K (Dec 20, 2007)

The 'high' tanks are harder to properly filter, IME. I would get a filter that has a long intake, perhaps even a small canister, so that the water all the way at the bottom is included in the filtration and water circulation. 
I aim for 10x the tank volume per hour, with filter and power head(s). Keep the water movement at the surface to a gentle ripple for good oxygenation without wasting too much CO2. 

20 gallon tanks, therefore have something close to 200 gph. You will not find this on filters labeled "for 20 gallon tank". Read the gallons per hour to find out more real info about the filter. 

For a specialty tank, I have a river tank for hillstream fish. This one has close to 400 gph.


----------



## Alexpatrascu (Feb 9, 2010)

I have a Eheim 2217 on my 50 gal(that's 5x the tank volume per hour) and I think there's enough flow.....


----------

