Eheim filter

[Andrew_W]

I got a Eheim 2008 internal filter, my questions

-can I put it lower in the tank then 1cm below water level?

-I plugged my Yeast style Co2 system into the diffusor thing, is that ok?

-how long before I can remove my old filter? (currently both are running)

[Lady-Lene]

If you placed the media out of your old filter into your new one you could take the old one out.

[SpidersWeb]

You can put it whereever you want but remember a few points,

if you're using it to pick up oxygen, its needs to be near the surface or it wont suck any in, not a drama if you're not using it to make bubbles.

If its feeding the CO2 in, you want it as low as possible, otherwise the CO2 will just diffuse in to the atmosphere. If the CO2 is being diffused by the filter, and you're getting about a bubble a second then keep an eye on your pH, if the pH changes by more than 0.2 a day you'll want to buffer the water or lower the CO2 level.

To keep oxygen in the tank, you'll want at least some water movement on the surface. If the fish start gasping, you'll need to increase the surface movement until they can breathe easy. With CO2 you want to least surface movement possible, without the fish suffocating. Plants produce O2, but its hard to get a perfect cycle going, especially with a yeast setup, so water movement will be needed.