Ulta beauty has its own chain of products which are very reasonable and very good. I am a big fan of Ulta products. I got this brush and sponge cleaner a month ago and i am use it soo much. Its so good, it leaves my brushes clean and clear so easily.
I just spray two times on my brush and rub it on between my fingers and wash it. I leave them to dry overnight on a towel under the fan. I do the same with my beauty blender but I use a little more of the product. It comes in a travel size too which i carry in my to go kit.
Its for only $10 and lasts for longer than any cheap drugstore cleaner. Its easily available at Ulta and i would definitely buy it again.