September 2016 update - about 5.5 months.
I've been very busy with home renovation, so had no time and energy to visit to pet shop for almost 3 weeks. And nothing bad happens actuaaly when I saw the tank yesterday and do maintenace. Of course, a little bit more BBA than usual, but I'm still think it's under control. Photo taken before maintenance with dirty glass:

60x30x36 - 6 months by
Alexander, on Flickr
For me nothing really bad in the state of the tank. I've done the maintenance, prune some plants and clean external filter. This time I've decided to set it up with media exactly as manual recommends (only active carbon I'm missing). The major change I've used bio-media plastic balls for second tray, as it should by the manual. So far all those years the canister have been working without those balls. I can't explain, but recently reading about sumps and refugiums, and how some big Amano's tanks have set up, I started to think I need more bio-filtration in my own tanks, rather than mechanical filtration. I expect to see better control over BBA, which is very possibly related to big amount of fish (about 20) and constant over feeding by pet shop staff (they simply don't want to hear my arguments about overfeeding). So my plan is to experiment with bio-media and see whether it's good for this particular tank with regular maintenance, and maybe I can start to do maintanence every 2 weeks, if it works.
Anyway, so far tank looks more or less OK after maintenance:

60x30x36 - 6 months by
Alexander, on Flickr
I'm startig thinking about rescaping it as riparium with rich emersed part, maybe fill the tank on half and make small waterfall with water from filter outlet. Also the fish. It's nice, but somewhat pale, I'd like to put there something more colorful, maybe cardinal tetra.