2nd filter - can it hurt?
Last week during my monthly filter maintenance my eheim 3e didn't want to start up again. I had found three pieces (the "float assembly") floating in the filter water. To avoid anything bad, I quickly hooked up a spare 2213 with 1/3 of the bio media from the other filter figuring it might take me some time to get the 3e fixed.
I called eheim technical support and they were able to help me and by the afternoon I had my 3e working again.
Now I have two filters running. The 3e is hooked up to a lily pipe and the 2213 to the spray bar it came with.
Is there a reason why too much water movement is negative? One concern I had was that it looked like the CO2 bubbles only made it to one side of the aquarium, because the spray bar is creating a strong cross current.