The barbs aren't completely settled in yet, so it'll be interesting to see if/ how their behaviour changes as they get more comfortable in their new environment. Most of them are still doing what I think of as the 'new fish dash'. Which is swimming up and down in the area of strongest current (the back wall of the tank). When they're not doing this they seem to swim in a slightly more nose down position. And they seem to have a stop start swim pattern. Whereas the rasboras are definitely horizontal and more 'pootley', just keeping up with the current, but not then moving quite as quickly. These two swim positions make sense when reading up on their natural feeding habits. Rasboras are surface feeders, whereas the five band barbs are substrate feeders. Again this was really obvious when I fed them. On Monday I fed a generous portion of flake, assuming that the barbs would have some. I'd read that barbs don't do well if fed only dried food, but I didn't realise that they wouldn't even recognise flakes on the surface as food! Having overfed the rasboras, I think didn't want to try a different food (which I know the rasboras would have gobbled as well). So by the time I fed again on Tuesday evening, the barbs seemed pretty hungry. This time I fed some gel daphnia. I tried to squidge it out of the packet in little bits and spread it around. The barbs waited till I was out of the way and then dashed out. They went completely head down and then moved around picking at the food on the substrate, or plants. The rasboras again kept as horizontal position as possible while picking food up. If one of the barbs broke up a bit of gel so there were loads of bits in the water, it was the rasboras that would go for the bits. The barbs seemed happier vertical, picking off the substrate.
Because they have different swim positions, it isn't as noticeable that they actually have pretty similar body shapes.
The kuhlis are out more and more as well (well one of them is). I've seen them just chilling under the crypts or draped over the base of the bolbitus. I'm looking forward to getting more and they will be my next fish purchase. I asked when I bought the barbs if they had any kuhlis and the lady that served me offered to order some. So when I'm ready for my next fish, I'll give my local MA a call and order some kuhlis.
I've realised that although all my fish choices should be compatible, they all have different behaviours. I won't get anything else done once I'm fully stocked from watching fish!