I want to change HOB filters

Question
Hi. I have 2 10 gallon Betta tanks. I own 2 male Bettas. My tank came with the Whisper HOB filters and I want to change them to aqua Clears. I have 2 Aqua Clears 50 on my 29 gallon Oranda tank. How do I change the filter without messing up the bacteria in the established tank? I know that the Aqua cleras are better filters. Thanks Mike

Answer
Hi Mike,
I am not familiar with Whisper filters.  The best way would be to buy used sponges when you buy your Aquaclears.  Used sponges are full of good bacteria.  This way you would keep your water chemistry right.  
I would also like to add,  when you rinse a sponge, you rinse it in water that you have removed from your tank.  Never rinse it in hot water as you would kill the good bacteria in it.  A sponge is good for a very long time, until it is ragged, and falling apart.  Ask your pet store manager if he would take the new sponge, and replace it with one that is used.  If he is a nice guy, he will do this for you.
Hope this helps.
Lynda