ok the thing is if you mix neos you will in general be undoing all the years of work that was put into creating the colors there are now. i myself put yellows and oranges together and what comes out of that or for my any way was yellow orange shrimp, little darker yellow than what i started with and lighter orange than what i started with so i didnt get browns from them. if you cross rili with blue velvets you will undo all the hard work it was to creat a solid blue shrimp and they will start looking like rili again. green and yellow are not generaly the same breed of shrimp. most green that are sold are not neos like the yellow. what happens is if you mix them all together over time you will get the wild colored shrimp ie brown, and what has happened is they have lost all the color that has been worked to get. as for rili and blue rili that are not blue velvets yes, my red rili is how i ended up with my blue shrimp but the blue velvets are a much better blue for the most part and breed true, my blues that came from my rili do not breed tru i can get blue, an aqua color blue, blue with red marking, red rili, and what i call purples due to the tint of the flesh.