Filter

[raytan12]

Is it ok to use power head filter for planted tank? will it cause loss of CO2. i'm using overhead ext filter, not good rite? so should i change? what benefits can the int filter give? what should i look out for? Thanks... for your kind advices

[vinz]

I'm using 2 Ehiem 2006 internal filters in my 1m planted tank. If you want to use int. filters in your tank, you have to make sure that its heavily planted with moderate bio-load. This is because int. filters do not handle as much bio filtration as ext. filters due to their size and filter media. You will be depending on your plants to handle the ammonium and nitrates. The main function of the int. filter in a planted tank is to circulate water and mechanical filtration.

Most int. filters allow you to direct the flow of the output, so, as long as you do not direct it at the surface and cause surface turbulence, you won't have more CO2 depletion problems. Also, don't use the airline to aerate the water.

Other things to look out for:
Accessories - you will have problems connecting additional accessories like CO2 reactors, surface skimmers, etc, to most int. filters.
Ease of maintainenace - most int. filters require you to rip out the whole thing from the tank, unplug from power and bring the whole thing to the tap to wash. I like the Eheim ones cos they allow me to detach the media compartment and impeller from the main unit. This way I don't have to fiddle with suction cups, power cables etc just to wash the damn thing.
Power - don't get too powerful. If the water circulation is too fast, the plants have a hard time absorbing the nutrients and then you get algae. Algae also has a tendency to grow near the filter output, so I suggest putting nutient sponges like h.polysperma near the output. The mass of foliage is also great for hiding the filter.
Aesthetics - too big, hard to hide. Greenish ones easier to hide behind plants. Black ones can merge into dark backgrounds.