Looking after Nimh stick packs - seeking advice

[Nige]

Chaps,

I've got five Team Orion 4500mah Nimh stick packs http://www.modelsport.co.uk/index.php?product_id=29664 but have noticed that when charging they don't go to full capacity. I did assume it was because I hadn't used all the power so they just needed topping up when I recharged them, but now I am not too sure. So I've gone and bought a Nosram Gravity Stick Pack discharger http://www.nosram.com/en/products/chargers/discharger-equipment/produkt/nosram-gravity-stickpack-discharger/details/ And I have an Ansmann XBase Deluxe charger http://www.fusionhobbies.com/Ansmann-Racing-xBase-Deluxe-Charger-p/ar151100001.htm

So I'd appreciate some advice on what is the best way to maintain my batteries. Please no signing the praises of Lipo, I'll be staying with Nimh for the time being thanks.

After racing should I just leave my batteries // charge them to xx mah // discharge + charge them to xx mah? And then the day before racing just charge them // discharge, then charge..........or something else?

Cheers fellas,
Nige