Yeah, for the best interest of the fish I think you should probably get a more accurate test kit.
Green water usually will indicate an algae bloom. Which is freeflowing algae thats not ancored down. This would indicate an abundance of ammonia or nitrites in the water. This would cause the fish to be very lethargic.
But like I said prior, Something spiked. Do 2 25% water changes today and 1 everyday for the next couple days. Be SURE that not a flake of leftover food is left to rot. If the tank receives any natural sunlight, You should prevent that. Leave lights on for no more than 6 hours a day.
I wish you the best of luck, Sensitive fish going through a nitrogen cycle is very harsh on them. I hope they make it.
And dont mess with the filters.