The Two Little Fishies BettaMag has been specially created to clean tough stuck-on dirt from Betta, Goldfish bowls or Pico aquariums; since the NanoMag moves the entire aquarium when cleaning these smaller models. This BettaMag window-cleaning apparatus has the umph needed for cleaning glass up to 1/8" to 1/4" thick. The BettaMag also glides across the curved surfaces of fish bowls, wiping off algal films with ease, and it's so much fun to use, you just might have to take turns!