Dyes:
+Gives a solid color look and can make your res UV reactive.
-It stains the loop. Its not like a permanent stain that leaches into the plastic. The dyes are not dissolved but particles so that ends up sticking to the side of tubing and blocks. Regardless, it leaves color on your tubes.
-The loop needs to be flushed multiple times to get rid of the color. Since the dye doesn't actually dissolve into the water, its hard to wash out but you might not care.
-It leaves residue. When it dries, it leaves residue for you to clean up. When I change water I usually get it on my hands and a bit on my case and stuff. I usually just leave that to dry because im using demonized water right now but there was a time I had to wipe down all my...