water circulation

Question
Hi, I have a octagon tank that measures 1 foot diameter by 18 inch. high, about 10 to 15 gallons. this tank was a saltwater tank in the past, but i have cleaned it very well. I am running a Aqua-Tech 5-15 power filter(rated at 100 GPH), and a under gravel tray with a Aqua-Tech power head(rated at 170 GPH). I have used power heads in the past with good results in rectangular tanks 30-60 gallons, but in this tank the water is really moving the plants (plastic) are waving around and bent over a little bit from the current. Is this to much circulation that will stress out or tier out the fish?  
I don't have any fish yet so any suggestions would be nice .

thank you , George  

Answer
Hi George,

I just wanted to tell you that the person I was talking about who had a similar tank recommended you leave the powerhead in place. I don't believe you can manually adjust the flow, but maybe if you turn the nozzle so it deflects against the walls of the tank, you might try that. Also, I forgot to mention, if you do decide to try using two filters, stock one with biological media such as ceramic rings (Hagen makes something called Biomax that I especially like) and sponges, and reserve the other one for activated carbon, if that is your intention. Most filters just give you a bit of blue floss and carbon in their cartridge on which to grow the beneficial bacteria. Then you're usually supposed to discard them! That's why I like using Hagen's foam sponges (for the AquaClear filters) and their bio-media - I rinse them in aquarium water instead of replace them.

The AquaClear filters by Hagen really have the best 3 step filtration of any hang-on power filter I've seen. That's probably why they are a little bit pricier. I just modify whatever filter I have to use their media, which works too.

Take care!
Nicole