Originally Posted by jestes
It may have been a glitch with the forum, because I didn't get the email saying you'd replied. Anyway......
Bio filter material will increase nitrates, because its supposed to. That's the end process of the nitrogen cycle, and nitrate is far less toxic than its precursors. Plants should help with your water quality, plus if you don't overstock the pond you shouldn't have much to worry about.
I haven't used one of those Tetra filters, so I can't really offer any comment in it. Do you have a local pond/water gardens store in town?
Okay I have done a lot more reading and i see what you are saying about bio-logical media. I don't believe that my pond will be over stocked, let me know what you you think. A 300 gallon pond with maybe 4 fancy goldfish and maybe a few minnow sized fish is all. Also if frogs from my area like it they might join in. and they will be a fair number of plants I hope. I've still got a lot to learn, but I thank you for helping out and speeding up the learning process for me.