Hi Neil, now - as far as I am concerned you and all on here seem to know a darned sight more about fishing, bait, rigs and so on, than me. However what I'm gonna say may be helpful, it may not - if the latter, then just ignore it! And I'll go and sulk in the corner somewhere!!! LOL
If you look at the "Used Tackle" ads in the fishing weekly's you will see they advertise "10 bags of groundbait for ?10" Now, at a quid a bag, one can't go wrong as far as I'm concerned! I order mine from there and have thus far received an equal amount of two different types: (1) 'Brazeam' & (2) just called 'Strawberry'. They come in 1 kilo bags. Brazeam contains Mollasses, and the latter is self explanatory. They are quite a fine mix, but mixed together (one of each for eg.) with the appropriate amount of water, they bind together pretty well and the 'sweetness' that bream love can be enhanced by a syruppy flavour such as strawberry or banana - which in turn, I find, binds the mix together even better.
As a further attractor I will add x-seed which contains everything and which I get from "Carp-Lines" And it still binds together for distance catapulting. As has already been suggested, perhaps larger amounts of seed, particles, etc, could be spodded out.
I should add that though they cost a quid a bag, there is ?5 postage to be added, but I always make the point of ordering a few other smallish items to make it more cost effective - if you see what I mean?