Fish 'R' Fun Green Killing Machine Internal UV Sterilizer with Power Head, 24W Upto 400 Litre

I hope this is useful information for those who are contemplating the purchase of this item. I have owned the smaller 9W version of this 24W uv sterilizer and it was also very good. I never needed to replace the lamp and it did its job for 3 years. The flow rate was very gentle however and not sufficent to circulate my 165 litre (36 uk gallon) aquarium so I used a seperate small powerhead to provide greater flow. The 9W version broke after 3 years as the cable entering the pump unit broke where it was connected because the cable bends repeatedly at this point. Greater care could avoid this happening but I did not realise. When it broke the green water returned again shortly afterwards showing that it had been working effectively even with a 3 year old 9W uv lamp. This larger model cleared the green water within 3 days and a further improvement in clarity resulted after a week of use. The flow with the larger 24W model is much greater and perfect for a gentle flow in my 165 litre aquarium. It does have a larger body and so there is more to accomodate within the aquarium but this is not a problem for me as it fits behind the same rock as the smaller unit. Interestingly, the point where the cable enters the pump unit has a reinforced connection which bodes well for longevity. Also worth noting is that the transformer is very heavy and cannot be left hanging as I did with the smaller model. Luckily the cabling is long enough for me to fit the transformer within the cupboard underneath my aquarium so there is again no issue there. Importantly, I recieved good service from Rocket Aquatics and the sterilizer was a brand new one in new packaging and arrived swiftly. On 01 Jan 2016 I had bought a 700IF from All Pond Solutions which is a 700 l/h internal filter with 9w UV steriliser but this was supplied in opened and damaged packaging and was not working. It was sent back for a refund which after much prompting eventually arrived on 10 Mar. I have found that when the water flow on this 24W reduces I can back-flush it by disconnecting the pump and reversing the flow while holding the pump onto the light unit. This seems quite easy to do. Also, I needed a cable tie to secure the unit to a rock in my aquarium as I found the sucker ineffective in my application.

I hardly ever write reviews but feel that this product warrants one. After weeks of struggling with my 330litre heavily planted, freshwater tank with bacterial and algal blooms I was at my wits end. Water parameters were all good and I’d tried various filter media, bacterial boosters, clarifiers and water change regimes to no avail. Moving the tank out of any light wasn’t an option so I’d got to last ditch attempt and thought this was worth a go. I thought the price was low and the concept too simple, why didn’t everyone have these as standard if they’re so good?? The answer is they should!! Within 3 days my tank is crystal clear and I can see the colours of the fish clearly and it no longer leaves me frustrated looking at cloudy water, it’s really made me love the tank again. The unit itself is smaller than I thought and is virtually noiseless with a simple light to show when it’s working. Once my tank has stayed clear for a week I’ll be switching this to a timer and running 8 hours per day to preserve lamp life with full running at the first sign of a problem. This is a great piece of kit - don’t be put off by the reasonable price, the name or the fact that many aquatics shops will say don’t bother or direct you to a much more expensive unit. The proof is in the results which are crystal clear. If you’re considering buying this - do it!

Update: It seems the electronic quality of this unit isn't up to much. This power unit has burned out. Luckily for us not catching fire or causing any damage. We noticed the burning smell and tracked it down to the UV filter. I would definitely not recmmend this product. It's a potential fire hazard. Had a thick 'pea soup' aquarium for 2 weeks and tried everything, including chemicals, daily water changes, no light and feeding to clear, but nothing worked. I bought this light with little expectation, but it started working within hours on a 350 litre aquarium. 48 hours my water is the clearest it has ever been. Highly recommend as an investment.

This has done a pretty good job of reducing the cloudiness/greenness of my 125g tank. I know it's undersized for my tank, but it has done well. Easy to assemble. Pretty solid. Nice. Cannot fault it.

Tried an external UV light as water would quickly go green after cleaning but it leaked and flooded the room so this was the next best thing. First one came and lasted a few hours before it died, most disappointed and wasn't going to bother with a replacement but I'm glad I did, refunded after returning the faulty one and gave it second chance. Easy to install, 3 wires go to a block that has 3 connectors all different so you can't make a mistake. It is quite large but not to large for my tank, it's virtually silent and has quite a low flow rate which gives a nice trickle and the water has had a noticeable change. I would change about 30% of the water every Saturday as well as vacuuming the gravel (Fluval FX6 gravelvac is superb) but by Wednesday the water would start to green, not sure if it's tannins from the wood, the tank is not heavily stocked and is not in direct sunlight but the water would quickly green. This has made a big difference, now after 3 weeks'ish I've not had anywhere near the level of green and the water is clear and crisp after two weeks without a water change. Edit: after nearly 2 years without issue I noticed the glass getting some algae on it and the water was going green a couple of days after weekly water changes. Even though it showed it was still working I thought I'd try a replacement UV Light, glad I did, I can't believe how much the water flow had slowed down, although the flow is a low trickle it's far faster than it was, I'll see how long the replacement light last but nearly 2 years I'm very pleased with.

After having read a lot of reviews on these, we decided to try one. We have a few aquariums and suffered with the usual algae issues. So, after having run this for a while now in the tanks, I have to report, it just doesn't really work. We are still having algae issues, and, although we read up a lot about this device, and saw the pictures other users put up, for us, for some reason, it just doesn't work. We were struggling with hair and black beard algae, so, we decided to go full strip down and start again, but this time, adding this green killer. For the first few weeks, perfect, no issues, and we honestly thought this device was the godsend we needed. But, two weeks later, and our tank again is suffering the same issues. Now we stripped EVERYTHING, renewed EVERYTHING, so we can honestly say that we took all precautions to make sure NOTHING that went back into the tank would have been "contaminated" with old algae. But, unfortunately, and its a shame to say it, but for us, this just doesn't work.

i have used these for years now and they really do work - i would recommend to always get the larger one not the smaller one you will get better coverage they flow can be turned down with the little twist knob at the side but you need to be very careful you dont snap it or you will need to by another one you can buy replacement bulbs - it keeps the water crystal clear once it gets working and does help with the cleanliness of the water quality and it is very quiet - the durability is excellent please not it is very big so might not be suitable for the shawoller tanks

We have a 240lt tank in which we keep some very large goldfish. We've had a persistent suspended algae problem for months and tried absolutely everything to get rid of it. Constant large water changes and using green water treatments. Nothing made much of a difference, and if it did, it wouldnt last long. We could barely see the fish in the tank, the water was that green, I was heartbroken. We researched a bit and found out about UV Filters. Found this product and thought, let's give it a go. We received it very quickly, set it up and within a couple of hours the water had cleared noticeably. We set it up on Friday afternoon, and then we were away for a couple of days. When we got back on Sunday evening, the water was clear, I couldn't belive my eyes. I could actually see fish! Since then, the water has gotten (and more importantly STAYED) crystal clear. I would recommend this product to everyone who owns a fish tank. Thanks so much!