Maintaining Tension in a Single Speed Chain

[BannanaMan]

Recently I took the bike into the workshop because the Shimano Nexus hub was playing up. Whilst they had it in the mechanic put a new chain on. Unfortunately the chain includes all the links that I paid for consequently the new chain is worse than the old one was.
If I had done it myself I would have bought a single half-link and used that to substitute for one of the links.
The mechanic seemed to suggest that I should consider a device which looks like a derailleur arm or to use a complete half-link chain.
Another option is to change the ratio of Chainring to Sprocket to negate the problem.

Is there anything wrong with using a single half-link in the chain?

 

[FrankCrank]

Your description is not exactly clear, but to answer the last question, half-links are fine for this application.

 

[lenfield]

Why not try taking links out of the existing chain? If you can't get the tension exactly right you can buy a single half link for it. It would be cheaper than buying a whole new chain.

 

[FrankCrank]

....the other thing is Nexus, as with all internally geared hubs, are fitted to horizontal dropouts, to allow correct chain adjustment.
The Nexus could of course have been retro fitted to a bike that had vertical dropouts, in which case it gets more difficult.
The 'magic' gear can usually be found with a combination of swapping out rear sprocket, a half-link, filing flats on the axle, filing the dropout to elongate the hole.
An element of luck is needed, but can be done