I haven't tried the age old in hydroponics, but I do use compost tea and fish waste as my nutrients in hydroponics. It's referred to as 'bioponics' or 'aquaponics'. The key to using organics in hydroponics is the biofilter or grow bed. That's where the micro biology thrive. Without them it won't work.They convert the organic matter into plant food. It's also important to provide oxygen to your reservoir with air stones. Having fresh oxygen in your water will prevent the bad bacteria from growing.

Here is a link that might be useful: Urban Garden Aquaponics