With runny poo I wipe it off with a bit of loo roll. Don't worry if you can't get it all off, the really liquid stuff will wash out easily

Alternatively you could use flushable liners, but I found that they clung to DD's bottom and seemed to make her uncomfortable.
I use ecover for my other washing but have found that it leaves my nappies a bit whiffy - I tend to use Bold infusions for about 2/3 of my washes, with ecover for the other 1/3, and I alternate between 40 and 60 degree washes.
I'd recommend a large bucket big enough to see you between washes (my bucket isn't big enough and I haven't got another one yet - apparently Wilkinsons is good) and I really recommend a nappy net - picking nappies out of the bucket by hand when they've been festering for 3 days isn't a pleasant job

The nappies will wash themselves out of the net during the cycle