After a 60 degree wash with prewash with non bio and a teensy bit of fabric conditioner mine still smell of amonia <gag> I desperately want to keep on with them but cannot stand the pong. I wait 2 days between washes to accrue a full load usually so they are not sat there a week or anything. The stench when I put them in the machine is overwhelming but better although still present when I take them out. Oh and I tumbled with bounce today as well...
we use a biodegradable nappy soak from here and never had any smells at all even with non-bio - they always smell lovely and fresh. And I have boys too whose wee is supposed to be stronger than girls (truth??? who knows!)
Now I am by no means an expert as I am only 39+5 with my first, but from hanging around on here I know that BigBadMousey will probably come on and suggest that you try stripping your nappies, so I shall save her the hassle of writing out the instructions as I have it already saved in one of my 'watched' threads for later! (I hope that I am right with this!!)
Soak them in white vinegar and cold water (500ml bottle of vinegar and top up the nappy bucket with water) overnight. Then put the whole lot in the washer, do a prerinse on cold, wash hot with a full dose of biological detergent. Rinse two times with warm or cold water to shift the detergent and the nappies should smell ok.
first i rinse all the nappies under the cold water tap (not hot - it sets stains). then i put them all in the nappy bucket which is filled with cold water. i don't use essential oils cos they can cause the nappies to start repelling water or vinegar or lemon juice cos it can damage the fabric. i wet pail cos it breaks down the urine and loosens stains so the nappies last longer. i don't soak wraps though cos this affects their waterproofness.
i try to do a wash every day because the longer nappies remain wet the quicker the fabrics will break down. i do a prewash with non-biological (biological washing powders can damage nappies) detergent a 30 degree wash with half a tablet or 1/4 the recommended amount of powder/liquid (we use non-bio liquid cos powder usually contains brighteners and perfumes which damage the nappy) and an extra rinse if the final rinse of the wash programme still had suds in it. don't use fabric conditioner cos it coats the fibres and so reduces absorbency. i hand wash wraps cos it makes them last longer.
i'm another fan of line drying as much as possible, but if not then they go in the airing cupboard. i don't put them directly on the radiators or tumble dry as this can damage them in the long run. also tumbledrying can make them hold their smells more. after i've hand washed the wraps i wipe them out with a towel to remove excess moisture and dry them as per the nappies.
Oh and it might sound bizarre but i got this tip off babykind. to keep your nappies soft the most effective and eco-friendly way is to catch some rain water and soak your washed nappies in it before spinning and drying as usual! We've got a waterbutt so i just soak the nappies in water from that.
After stripping your nappies you need to adopt a washing routine that involves a cold riinse at the beginning, doing a hot prewash at the start sets in the stanky amonia pee smell - a cold rinse will rinse out the yellow stuff before a lovely hot wash. I do this and never have wiff issues - odd times like once every 6 weeks after doing this i might put them on an extra wash with no detergent for the hell of it.