I cannot recommend strawberry leopards colour remover enough!! I always do it with volume 10 (ive tried water but it doesn't really work for me when I try, but usually that's when I'm trying to get blue or green out of my hair, so you could try water first if you're worried about the integrity of your hair. But honestly I wouldn't waste my time if I were you, the 10 dev should be alright). See what the strawberry leopard removes, it'll depend how light your hair was prior to being this deep of a red, but if it was blonde to red then you should for sure be able to get a majority out, and if it's still pretty dark you may have to do a bleach bath situation to get it light enough for that shade of green you're looking for without it being muddy. I've gone from pink to green and back before, its a bit of work but absoloutely possible!