The smell of any MW culture can take some getting used to
At best it smells like a lot of yeast -- like brewing beer. At worst -- well lets not go there. Best to keep MW cultures away from sensitive noses and queasy stomachs. It has taken my stomach quite some time to get used to especially when cleaning out one that has gone bad.
The medium you use also varies. Lisa uses Weetbix and I use bread. I've never used Weetbix and I think I'll give it a go. The principle is the same and the end result is MW's. But they do need yeast to thrive. With bread I find I don't need to add any yeast and I can stretch out the culture by adding another slice of bread on top of an older one, sometimes having to add a little water. However every 10 days to 2 weeks I make sure I restart some cultures to keep them going. You can also put a few established cultures in the fridge as a back up. Just make sure no guests decide to eat the special breakfast or takeaway you have in the fridge
They will last for some time in the fridge (I've kept them for months) and they don't smell since they go into hibernation or something. To kick start them off again just take them out of the fridge, put them into a warm place and add a little water. I use aquarium water or aged water not tap water.
A culture can go for some time but it does need to be looked at regularly to see if it hasn't gone off and died. We are still on the same culture we got over 2 years ago. I always have about 6 active cultures going and one or two in the fridge.
I harvest mine with a toothpick scraped along the side or if it is a very active culture and they crawl all up the sides and lid I'll dunk the lid into the water. You do need to spread them about the tank like Lisa says and not put too much in.
MW's also attract all sorts of other creepy crawlies. Ants and Flies (and subsequent maggots) for one. Although disgusting the maggots make great adult betta food. Ants are quite simply annoying.
Pat.