Aquatic Experts Bio Balls Filter Media Bulk, 1.5 Inch Large Bio Balls for Pond & Aquarium Filters, Pond Filter Media for Outdoor Ponds, (100 Count with 10" x 12" Mesh Bag, 1.5 Inch)

So far so good. I am very pleased with this system. it is working very well with no complications.I am using it in a 300 gal pond it's just great.

works good gathering a lot of the algae and debris

They seem like a good product but we're using them in conjunction with matala pads to biofilter a duck pond and I'm not sure we've got enough filter material in the bog pond.The balls float and we originally weighted the bags but then tied them together as a last filter before the waterfall without the weight. Can't say I've seen a difference in water quality no matter where they are but I'm pretty sure I just need a lot more filters to grow good bacteria.We are trying to handle filtering around 850 gallons of nasty duck water with up to 8 ducks, soon to be 7 once we rearrange a boy to a different zone.I think these might be better suited to a cleaner environment, like coi or ornamental ponds.

What a brilliant product! SO much better than those old dirty lava rocks. Easy to clean with a good hose. My pond water greatly improved after adding these

I've used the bio balls that snapped open a few years ago. They did a great job but we're almost impossible to clean. These are a great change if only for the ease of cleaning. I use them inside the pump box as the final filter in my the 3rd portion after 2 pre filters. Extends weekly cleaning to 3 weeks in Koi pond.

Good quality

I have a similar product that came with the filter & wanted a backup. The original product is a larger bag with a draw string. This one is a smaller bag with a zipper. It doesn't actually fit in the filter as well a it should. Disappointing.

Great Product