Its got pull out hangers on it's sides so can vary. Look at the description of the different sizes of lights. That should tell you the minimum and maximum it will size to. The actual strip is the minimum size width listed. So if you have a 24" wide tank, you could use either the 18-24" or the 24-36" one. But the 18 to 24" one is an 18" LED strip with legs that will extend it out to a 24" tank. The 24-36" one is actually a 24" strip that has legs to extend it out to the 36" length.
If you mesure the size of your tank width, you'll want to get a light that is listed as fitting that width. Unless you plan on moving the light around between different aquariums, you set the leg width one time and then leave it there.
answered 1 year, 8 months ago
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