Im getting two small 15 gallon clear pop up ponds to put out on my back deck, and was wondering what would be the best internal filter? I have no idea, so any advice would be awsome.

Jess, the only internal filter I know is a from Laguna, I am just not sure if it fits into a 15 gl pond. Check it out....
http://www.bigalsonline.com/catalog/produc...id1=2153;pcid2=

There is one other kind I once tried, but it was even bigger than the one above, and had a flat rectangular shape to it. Way to big for a small pond.
The one above comes in different sizes, maybe one will fit....

What did you end up doing? I was just given a 28 gallon pop up.