AquatopReplacement 7W UV Bulb – Fits FZ7, PF25UV, PF40UV, SP7UV, UVE7, Energy-Efficient Lamp for Aquarium Filter Pump, R7WUV-SQ

Honestly, I'm not sure if it is the bulb or the filter. The old UV Bulb was burnt out though, and worked fine until it went out. This bulb would not come on, and took me quite some time fussing with it before it finally made connection. It has gone off 2-3 times since purchase, but it has lit back up each time easily if I loosen the bottom of the filter and give the socket area a slight tap.Bottom line, either the UV40 (also purchased from Amazon, which I chose NOT to review as it annoys me with its noise, so the review would have been dreadfully harsh) or the replacement bulb for the UV40 are "hinky". One of them is not going to last very much longer.When these UV sterilizers work, they do their job well. You can tell a marked difference in the quality of life for your fish. In my case Discus, who were constantly feeling under the weather, not eating too well, but have been just the opposite from about a week after adding this UV40 power filter along with the other one.

The AquaTop ATP Bulb Rplcmt UV 7W is the must replacement bulb if you have the filter. Easy install and lasts a long long time. Dr GF

Worked fined! Ordered it again for the second time since my last one was very weak and as always works like a charm

A little flimsy but it works great and is nice and bright.

Thank you very much for all the great work and for delivering my item on time and as well for making sure my item was very well protective and not but not least the delivery man thank you very much for your hard work

perfect replacement for filter

Works very well.

This product arrived very quickly and packaged in an ingenious way that prevented any harm or damage to the lights. They are replacement bulbs so not a lot to rave about there. I was truly amazed at the short amount of time it took to get this item, I think it took about 3 days total.