Micro worms can only be fed for up to 4 weeks, after that you really need to switch to a larger food. I like to feed my fry a mixture of microworms, vinegar eels, walter worms, and bannana worms until they're about 2 weeks old. Then I phase that out and begin using frozen or live bbs until about 5-6 weeks old (depending on size), then I transition to NLS grow, crushed atison's pro, and frozen daphnia, from then on I feed that until they're big enough to eat regular pellets and frozen foods.
I'm not sure what you mean by having a tank for cultures. You don't need a tank to culture foods unless your culturing something like daphnia. You can google how to make a DIY brineshrimp hatchery out of a plastic bottle. It's very easy. Most other cultures can be housed in tupperware style plastic containers.
A 1:10 mixture of bleach and water is the best way to disinfect a tank. Scrub and rinse thoroughly with hot water then leave out in bright sunlight to dry for a few days.