# Reducing light intensity in Juwel tank



## Viv (19 Feb 2014)

I've got a Juwel Vision 260 that I want to reduce the light intensity on. Previously with other Juwel tanks I've just taken out one of the tubes but with this tank neither tube comes on if both aren't in. Raising the light unit isn't an option so I thought about putting a strip of tape along the underside of one of the tubes.

Does anyone know of a tape that will do the job? The tubes are T5 HO 54 w so the tape would need to cope with high temps as well as the humidity.

If anyone has got any other suggestions on how to reduce the light I'd be happy to hear them 

Viv


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## Fern (19 Feb 2014)

I'm not too sure about using tape on the tubes, but you could try using jewel reflectors clipped on upside down


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## AshRolls (19 Feb 2014)

I have the same problem and use a Juwel reflector, positioned underneath the bulb to shade the tank.

There is also a way of rewiring the ballast bar so that it only operates with one bulb, but this involves cutting into the bar and a bit of DIY knowledge.

*edit* Just seen Fern answered whilst I was typing my message


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## Viv (19 Feb 2014)

Hubby suggested I do that with the reflector! I'm not keen 'cos I'd get blinded every time I fed the fish. I suppose I could do this with the tube at the back instead. I think we'll leave the ballast bar alone! lol

Thanks for your advice 

Viv


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## Fern (19 Feb 2014)

I know what you mean about being blinded.....when I put a reflector like that on one of my tanks, I just quickly turned the reflector around slightly so I could see what I was doing , well it helped a bit anyway!


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## Edvet (19 Feb 2014)

Rap some small pieces of aluminium foil round the tube perhaps.


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## Ian Holdich (19 Feb 2014)

Fern said:


> I'm not too sure about using tape on the tubes, but you could try using jewel reflectors clipped on upside down



What a great idea!


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## Lee Sweeting (19 Feb 2014)

I used to have a jewel tank and also used the reflector to reduce the light. It worked a treat for me, although it is a little bright when you pop the hood open.


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## Andy Thurston (19 Feb 2014)

Put 2 reflectors on it


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## Ian Holdich (19 Feb 2014)

Big clown said:


> Put 2 reflectors on it




An even better idea!


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## Lee Sweeting (19 Feb 2014)

Big clown said:


> Put 2 reflectors on it


 

da daaa! Why didn't i think of that


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## Viv (20 Feb 2014)

I've turned the one at the back for now but I'll see about getting another reflector 

I don't understand why Jewel started making them this way 

Viv


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## Alastair (20 Feb 2014)

Id ring juwel and complain about the fact if you take one bulb out the whole unit doesnt work. I had a vision 450 and took off one tube from each balast to reduce lighting and it didnt knock the whole unit off. They may send you a new one for free if you send a nice email


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## Andy D (20 Feb 2014)

Worth a try but unfortunately this is how Juwel tanks are wired now. My Rios are the same. If one light is out then neither work.

Juwel used to have issues with units failing so perhaps this is how they have gotten around the issue?


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## Viv (20 Feb 2014)

Yeah I did that with my vision 450 but assumed there had been a change in the 'design' - this tank is a lot newer even though both tanks are T5. I might contact Jewel just so they know they're causing people like us problems! lol

Viv


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## mcfly (24 Feb 2014)

Maybe try some floating plants? They will certainly keep the light down an their useful for other things


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## ian_m (24 Feb 2014)

The Juwel units are wired like this as it is much more power efficient with electronic ballasts to wire the tubes in series. Only one set of high frequency tube drivers and electronic starter is required for both tubes. Duplicating the circuitry once for each tube will probably increase power used by 10-20%, as well as at least doubling the component cost.


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## Andy Thurston (24 Feb 2014)

> as well as at least doubling the component cost.


cost cutting by the maker, now your getting there


> Duplicating the circuitry once for each tube will probably increase power used by 10-20%,


 bonus byproduct of cost cutting, they can advertise as energy saving too.
I bet they still cost around the same too


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## ian_m (25 Feb 2014)

Big clown said:


> cost cutting by the maker, now your getting there
> bonus byproduct of cost cutting, they can advertise as energy saving too.
> I bet they still cost around the same too


Got me interested in cost savings.

A quality T5 HO 54W single ballast (ELT brand) is £36.
A quality dual T5 HO 54W dual ballast is £41.

Thus saving of £31, quite significant extra on £100 lighting unit.

Also single unit quotes 66W for 54W tube and dual unit 117W for 2 x 54W tube, thus 2 x 54W ballast consumes 15W more. 15W more is 15/1000*10*0.15*365=£8.20 a year more expensive to run. (10hours a day @ £0.15/KWh).

Thus dual unit save £31 initial cost and costs £8 a year less to run. Good reason enough for me Juwel's design decision.


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## Andy Thurston (25 Feb 2014)

Wow 2.2p per day and how do they compare on price to the old type unit?
I'd rather pay the extra and at least one of my lights stays on if a tube goes and you have the added bonus of been able to reduce light intensity when algae sets in without using pests like duckweed. Also juwel lights dont have a good track record, their ballasts are known for being short lived
Not much of a saving if you have to replace it every few years


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## ian_m (25 Feb 2014)

Big clown said:


> Also juwel lights dont have a good track record, their ballasts are known for being short lived


My first Juwel unit lasted 7 years and that was bought second hand. Current T8 unit is 4 years old and is about to be replaced this week with T5 hi-light unit.

Most Juwel lighting failures, according to local shop is people dropping the unit in their tank and water getting in, especially in older units where the seals fail at the lamp connectors and the fact that people fail to seal/replace the lamp gaskets.

If I had my way, and could get the Juwel units open (and sealed again) I would be to replace the Juwel ballasts with a dual dimmable version (about £50) so the tubes could be dimmed. There was a dimmable ballast I found based on 1-10V control and a switched one where you apply power for 0.6s, turn off and when back on cycles up and down brightness until you cut power again and it remembers that brightness.


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## Richard (1 Mar 2014)

Viv said:


> I've turned the one at the back for now but I'll see about getting another reflector
> 
> I don't understand why Jewel started making them this way
> 
> Viv


Hello Viv,
I've got a Rio 125 and I have algae issues although my tank is quite heavily planted with mainly Crypts and Anubias with some Vallis at the back.
I have started using the reflector on the back tube reversed but I'm not 100% sure how much it actually reduces the lighting,there is no light spilling out of the hood so I suppose it is still going into the tank although not sure if,perhaps,the intensity is lower.
I think time will tell in my case.


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