How To Use A Nitrazorb Pouch With Undergravel Filter?

[tricklexxx]

Hi everyone

Now this may be a daft question and forgive me if there are already answers on here that I've missed -

I'm trying to drop my Nitrate level using a Nitrazorb pouch (have upset my small tank slightly with moving fish to new tank and snail problem!). Where is the best place to position the pouch if using a undergravel filter/powerhead setup?

Is it best to mackle together some kind of chamber to house it in or just hang it in front of the flowing water?

Thanks!