It’s such a simple idea, but you’ve probably never thought of it before–why not throw a glow stick into your bathtub or pool to create an exciting, luminescent atmosphere?

The trend has suddenly become a hot topic in the Japanese Twitterverse, and over the past few days many people have been testing it out and posting pictures of their lit-up baths for others to be envious of. If you have some leftover glow sticks from a concert or party, this could be the perfect way to get rid of them. More pictures after the break.

Glow sticks are known as “Cyalume” (サイリウム) in Japanese, after the brand name of one of the chemical compounds used to make the reaction that gives off light. Here are some of the recent tweets advertising ‘Cyalume baths’:

▼”A glow-stick bath”

▼ “You should definitely try this–one glow stick costs only 100 yen [US$0.97].”

▼ “I wanted to try making one of those glow-stick baths, but somehow it turned out different from what I expected. Now I’m waving it while I watch a MoCali DVD.”

The next Twitter user provided detailed instructions on how to achieve a quality glow-stick bath:

“Correct sequence of steps to make a glow stick bath:

1. Buy a glow stick (it doesn’t have any batteries). They’re little tubes that light up when you bend them, sold for about 100 yen each.

2. Bend it to make it glow and throw it in your bath. If you’re worried that the liquid will leak, you can put it inside a Ziploc bag or something. Keep in mind that the liquid could be harmful to the touch. It’s VERY easy.”

▼”I got a glow stick → I bent it → I threw it into the bath → I turned off the light.”

As one of the above Tweets says, the liquid inside glow sticks has the potential to cause an allergic reaction in some people, so you should avoid touching it in the unlikely case of a leak.

What’s the coolest color combination you can come up with? Have fun testing them out!

Source: Togech
Images: Twitter (@s_mhnmd0617), ActiveDark