Awesome conversion! Never seen a dedicated 2x18w choke before! Surely it's an EC36 rebranded?

Thanks! These are a fair bit smaller than an EC36, got a few from some damaged Cooper modulars. I'd never seen a 2x 18W choke before either!

Is it a jewell aquarium? The HF lighting units have always put me off them!

After some swearing! ROFL , sounds like most of my jobs!!, great conversion.

Yes, it's a Jewell! I managed to haggle £100 off when I bought it as it was a display model, nothing wrong with it though! There's some pretty long threads on a lot of fish keeping sites with people moaning about the lighting units, and giving guides on how to saw the bottoms open to replace the ballast. I thought I'd go for a more permanent solution with mine though and I managed to open it along the factory seal so it looks untouched!

Haha! I can't do any job without getting slightly nasty, nothing ever goes to plan!

Looks good! I've seen the 2x18W ballasts about for a whole now in VS Tridonic and halvar!

Perhaps they're a new low loss range? Maybe a way round the bans we hope! Still see plenty of switchstart 4x18s being installed! Those 95s should be a good colour for the fish too!

Great conversion! Same lampholders as mine!

Could be Tom! They're fitted in all the Cooper 2' twin battens and 4x 18 mods now. I'm expecting them to switch to a different manufacturer though as Tridonic's magnetic ballast factory in Austria was shut down late last year!

The 95s do an excellent job. Give a nice natural look, almost like diffused sunlight shining down!

I used to have a bow-fronted tank and the lighting unit in that seemed to be OK. Not sure it was a Jewell tank though.

The thing is this : The new standards (read : bans) demands for efficiency are higher for higher power ballasts. for 18w ballast they demand efficiency X, for 36w the standards are higher, and so on

The standards also say that, if a ballast is running 2 tubes say 2x18w, the required efficiency is the same as if 2 1x18w ballasts would be running the 2 tubes separately. So, it is allowed for a 2x18w ballast to waste as much power as 2 separate 18w ballasts.....

The manufacturers jumped on this, and manufacture this 2x18 ballast. Its an extremely lossy ballast (it is more lossy than the old "inefficient" 36-40 ballasts), running at its thermal limit when used with 2x18w tubes at 370-400mA (yep some of those do overdrive the tubes a bit, but not too bad). Running a 36w tube on it will most likely slowly cook it

The same thing btw is happening with the 26w PL-C lamps, they have been separated from the 18w T8 to a ballast of their own

These losses can be seen at worse in 28watt 2D fittings, as most in the UK are fitted with a standard 2 foot, 18/20watt choke, running a 28watt lamp!

The 2D is electrically quite similar to the 26w PL-C. They are high voltage, low current (320mA vs the 370mA of the T8-T12) lamps. The same ballast running a 28w 2D or a 26w PL-C will waste only about 3/4th of the watts it wastes with a T8-T12