Penn-Plax Aquarium Bubble Disk Aerator - Air Pump Accessories – For Fish Tanks (Small)

I put these into 1 gallon bubble buckets and they performed GREAT!Lots of bubbles! They do not have weights though, so they float around a lot. No biggie for farmers but fish people might not like it.

This item bubbles just fine, keeping it sank is an issue, I've tried drilling holes in the plastic molding around the stone to release the trapped air inside...and they did, but the plastic is bouyant enough to float the thing right to the surface so, if you can use an air stone at the "top" of your tank...this is the one for you. GOOD LUCK, R.Tillery

I have a 75 gallons tank and wanted to give it better oxygenation, so I started looking for an aerator. I had to think a lot before deciding which size to get, and in the end I bought the 3" one. As others said, it produces an enormous amount of bubbles for its size, and it's perfect for my vertical aquarium, so considering its power, you might as well consider that the size is utterly important, depending on the size of your tank; I believe the 3" will work great for 100-gallons-and-less aquariums.The only disadvantage is that it needs some weight to stay down, I had to tie it to the bottom. Besides that, it's perfect, and having it for a week with 6 ten-inches goldfishes who usually make a mess everywhere, it was pretty much clean.

This thing is not weighted down at all. It floats. So.......you better have a large rock, shell, or some kind of decoration to weigh it down if you want it to work at all. I am so sad that I can't use this until I get some kind of weight to hold it in place. So disappointed.

Works great. Easy to install. Great product. Fish love it too. I do recommend it.

I have a large Koi pond with six air outlets and a waterfall that aerate the water. The fish have voted. They never seem to be around the round stone. The other five are ball and cylinder shaped and much cheaper

Excellent flow easy to use and heavy enough to stay on the bottom without being waited. I'm going to be buying more of these

After soaking the 3" stone for about 40 minutes instead of the 15 (because I forgot about it for a few minutes), I hooked it up only to be disappointed with it's bubble output. There are only a few bubbles that come out on the sides and not from the entire top or even a quarter of it. My 1 inch stone produces a hell of a lot more bubbling that this entire piece of floating junk.