Filter size

Question
I have a 29g tank and considering the Emperor or Penguin system. A salesperson told me to use twice the size for the tank, but will that take out too much good bacteria? TIA!  

Answer
Hi Melinda!
They told you the right thing.
You can never have too much filtration. I use a Fluval 405 cannister filter and a Penguin 350 on my 75 gallon.
I would get the Penguin 350 for your tank. It is rated for 70 gallons I beleive.
It will not remove any bacteria.
Good Luck!