i have just read through this whole conversation and, in my opinion, some shrimps and a betta are definitely your best bet. hexagonal tanks can be a nightmare to stock!! generally fish prefer rectangles as the increase the surface oxygen and provide more swimming space. the minute you go for any other shapes, you automatically rule out fish such as corys, danios, harlequins etc. so yes, i think you have made the right choice for your tank. check out the beginners threads on cycling etc. they will help you loads. if you really get into the hobby and decide at any point to get another tank, do try to buy a standard rectangular tank...it will seriously increase your stocking options!! for now though, i think the tank you have will be great with the bettas and shrimp.
ps - i have been to malta 3 times on holiday. it is a lovely place!
thanks for your suggestion! great that you enjoyed malta well i've just moved back from the uk, where i had 2 x 4 feet so not as such a beginner, just here at my mum's house i'm not allowed to go beyond the 40cm mark lol hopefully as they get to like the fish i can go once more for a 4feet - or maybe a custom larger hehe
for the time being betta and shrimps it is