Do I need a filter?

[tennesseemom]

I have a half whiskey barrel set up on my back porch with 2 feeder minnows that never got eaten in it. When it gets a bit warmer, I wanted to add my 3 guppies to it and that's all. I have some plants from my tanks and some driftwood. Do I need to add a filter? I have several laying around but where I have it now there isn't an outlet nearby. I could move it if needed.

 

[toddnbecka]

I have a small concrete pond in my back yard. I tried filtering it (one season) with a powerhead and flowerpot stuffed with bulk filter media, but it clogged up too quickly. Since then it hasn't been filtered, and water changes happen when it rains enough to overflow the top or evaporation makes adding water necessary. It contains a collection of hardy water lilies and some rosy red minnows for mosquito control that were left after a large catfish was moved out. The rosy's spawn every spring, and I net out most of the fry for feeders. The neighbor's cat also picks off a few, but the large adults are several years old now and still going strong.

 

[Sploke]

I would probably put in an airstone or something to help prevent stagnation, but with enough plants you should be fine.

 

[Turbosaurus]

I agree with sploke, you're going to want to do something to keep the water moving and prevent stagnation. Powerhead, airline, whatever. I a filter isn't needed, but you do want that water moving to facilitate gaseous exchange at the surface. I would also add some substrate just for the surface area for bacteria to colonize.