I have not tried it, but as long as it physically will fit into the fixture it seems like it would work. I am honestly not sure how much difference the 4w in output will make, but if the fixture will power it up then it will work fine. Typically if the ballast or electronics are not compatible with a particular bulb it will simply not work, so plugging it in will probably be the best test.
Can you help me with the UV bulb change on HW-304B?
I just got the HW-304B from Ebay and I think I got an used one with a non-functioning UV light. I have the manual but the instructions are uncomprehensive on how to change the UV bulb. Can you please help me with this?
The Fraternity of Dirt
If at first you don't succeed,,, keep kicking it RubberSideDownOnTheLanding, 2-75g planted, 5-55g planted, 5-20g planted, 110g w/30g sump, 8-10g, Refugium, doghouse/newbie 2012 update adding table top pleco pans & a 90g (Nutz)
525gph seems like a lot of water flow past a 9w uv bulb.The slower the water passes over the bulb,the more affective it will be.If the uv is inline,can you splice in a tee fitting before the uv and direct that into the tank cutting back on the flow to the uv ?