Aqua Ultraviolet UV sterilizer.. Why is the 25W and 57W same dimensions

[125mph]

I'm looking at getting a UV sterilizer.. I saw the 25W version is has dimensions: 20” x 3-3/4” x 6” .... but the 57W version also has the same dimensions...

While the 40W version is super long and doesnt fit my cabinet well.

Any reason why the 25W and 57W is the same size? Is the actual bulb of 25W and 57W the same size? If so, couldnt I juts buy the 25W and buy the 57w bulb instead?

 

[Lbrdsoxfan]

Search, this has been touched on before. Different ballast is why you can't do it. The cost to upgrade the hardware to a 57w setup, may as well bought it to begin with.

 

[Fishgeek88]

The housing is the same but the ballasts are different.

 

[Reefering1]

Not sure about the bulb, never had the 25w in my hands, but I'm sure the power supply/ ballast is different..

 

[Jamie814]

25 watt is a normal output bulb and ballast. The 57 watt is a high output bulb and ballast. 57 watt = more UV light in a smaller area which would allow for higher flow rates with the same amount of exposure as the 25 watt at a lower flow rate.