Neutrally Buoyant Water Ball

By Watermelon Ball

Add to Wishlist


For your next swimming pool game, toss around a Watermelon... Ball. Modeled after a real-life watermelon, this rubber ball can be dribbled, kicked, passed, and bounced—all under water. Fill it up with water and a little bit of air to make it neutrally buoyant—its density will match that of the surrounding water, so it doesn’t sink or float. Instead, it stays suspended in the H2O.

  • Materials: PVC/TBC, natural rubber
  • Neutrally buoyant when filled with water
  • Looks, feels, and behaves like a real watermelon in water
  • Passes up to 10 feet in water
  • Bounce against pool walls
  • Can be bounced, dribbled, kicked, and intercepted
  • Made in China
  • Dimensions: 3.94" x 8.07" diameter
  • Weight: 1.28 lbs.

51 Reviews (4.7 out of 5 Grommets)

Sorted by Rating

Excellent for play and teaching

9/1/2017 by Carole

A couple of years ago some of my children and nieces and nephews tried to make a neutral buoyancy toy with a pill bottle and a dime and an engineer cousin. He could explain it but we couldn't make it. This Watermelon ball was a fantastic solution. I bought three; one for each middle school family and took them to out family beach outing. WE had fun with them.More > < Less


Great Pool toy for everyone!!

8/23/2017 by Kathryn

I have purchased two of these unique and fun watermelon balls as gifts for families with pools. The balls are unlike any other pool toy that they have. Within five minutes, the kids had created games with the balls. Everyone got into the fun! Had so much fun with the first one that I immediately ordered a second one for a different family. Read the filling instructions carefully!More > < Less


Fit and fun!

8/16/2017 by Roxy

This ball is so much that fun I'm taking it away from my family for a little while and bringing it to my aerobics swim class. We can get fit and have fun too!More > < Less


fun Unique toy in pool

8/15/2017 by sharon

Used it at a house pool party. Everyone had fun. More fun when several in pool but can be used by self too. Not supposed to throw ball - we did not read playing directions until after swam. It is hard. You fill with water and air for the bouyancy you want. Works great.More > < Less


the kids love it!

8/14/2017 by karen

We ordered this for our grandchildren to play with in our pool. Our ten-year-old doesn't even have to have other kids with him to enjoy the ball and I'm so happy we found it on The Grommet .More > < Less

Items 21 to 25 of 51 total

How come this ball won’t float or sink?

About Watermelon Ball


Up your swimming pool game with the Watermelon Ball.

We’ll explain. Apparently tossing around a real-life watermelon in water as entertainment is a thing. They behave differently than most air-filled balls, so you can actually dribble, kick, pass, and bounce them—all under water.

The reason for this behavior—not floating, not sinking, and sort of suspending itself mid-water—is that watermelons are made of 92% water. That makes them neutrally buoyant. But real watermelons also break and make a mess...

The Watermelon Ball is made of tough rubber. You can fill it up with water and just a little bit of air to get it at the right buoyancy. Throw it up to 10 feet under water and combine elements of football, basketball, and rugby for some unconventional aquatic entertainment. Or toss it around outside the water, too.

Turns out no part of the pool is off bounds with this summer game changer.