BAITAI Internal UV Fish Tank Filter,400L/H 4W Aquarium Filter Pump,Turns Green Water to Clear,5-in-1 Filter Pump for 15-80L Aquarium,Flow Rate and Direction Adjustable

Bought this as I have already have a UV filter in my pond which have proven very effective and thought I would get one for aquarium.This unit is working and filtering the aquarium water very well keeping tank crystal clear.However, I would not purchase again and now question my choice as replacement 4W UV bulbs seem to be unavailable so once UV bulb fails will have to purchase a different unit.As others have mentioned there is no visible indication to show UV is working and instructions poor.Addition to above.I have been using this filter for six months now, it has kept the tank crystal clear and I have not had to clean the glass at all. Initially I was concerned that replacement UV lamp could not be found but, from this supplier I have been able to purchase a replacement.I have now purchased another of these filters for a different aquarium and that is working well. When I remove the unit to clean the sponge I turn it on for a second without looking directly at the lamp and can see that it is working.

My aquarium tank water has been the clearest it's ever been crystal clear and I love this piece of kit a must for any aquarium love it and lovely customer support a refreshing change today

Daughters tank was constantly green within a couple of days cleaning so bought this with good bacteria and its perfect

I was very pleased with this uv filter until it stoped working after just 51 days.

What a fantastic filter. This has made a big difference to my fish tank in just three days. I have struggled with green water for weeks, trying everything to remove it with no success. It is not crystal clear yet but definitely not far off. I cannot believe the difference it has made. I can now see my fish in the tank swimming around. This filter is certainly to be recommended.

Yes, I know it was cheap but I did hope that would actually work. It was a treat for the fish as was the Castle for them to explore. Alas, the castle is now green. The filter and venturi work well but it is let down by the poor UV lamp. I thought it was a dodgy bulb (it's not that bright) so I looked for a replacement. Just can't find one. You get what you pay for I suppose...

It’s quiet efficient and effectiveEasy to installMost importantly the fish congregate around it seemingly enjoying the water

This filter worked great for a month. CrystalClear water but after 2 months it keeps stopping and after I cleaned it out then it won’t work again. I’m having trouble getting hold of the seller for a return or replacement but apart from that it worked fine