I have been using a Growing Solutions worm tea brewer for two years now and I absolutely love it. I use to brew in a 5 gal bucket with air stones and an air pump and mesh bags. This worked well and any worm tea is better than no worm tea but I was not satisfied so I tried a few different brewer types along with different air stones and air pumps.
I found the Growing Solutions 10 gallon tea brewer. At first I was very turned off by the price but after reviewing the other commercial brewers in the market it did not seem to far out. I would have liked to have gotten a larger gallon brewer for the price but that would have meant larger air pumps and aeration disk which would have meant more cost.
These brewers are advertised on fine bubble diffusion. Each aeration disk disc has 4,000 engineered perforations (1mm in size) that provide consistent air bubble size and velocity. Also each disc’s perforations self seal when the system is off, preventing back flow of Compost Tea into the air manifold. I have noticed that this last point is very effective in keeping the air disk from getting nasty and full of tea or crude like many stones I had tried before.
The next component that I have really like about the system is the filter basket that is produced from industrial grade nylon mesh. This allows the water into the casting mixture in the basket but does not allow the castings back into the brewer. This is very useful since I use most my tea in sprayers and other brewers would allow to much casting mixture into the water and would clog up my sprayers even after screening it and this brewer keeps the tea very clean. It also have a nozzle on the bottom of the system making removing the tea much easier and also helps making cleaning the system very easy also.
Over all I really like my brewer and I am very pleased with the system but at a $600 price tag I would not recommend that ever home brewer jump up and go buy one. I would say that if you have a large greenhouse or commercial business like golf courses or landscapers then it can be totally worth the purchase.