Suitable for all temperatures, ideally wash in warm water. Use only one scoop (40ml) of powder and either place in the powder dispenser or pre-dissolve in a little warm water. Do not put the powder directly onto clothes. If clothes are very soiled, soak overnight or use ecostore pure oxygen whitener. Safe for septic tanks and grey water systems. We don't add anti-caking agents to our powders so it is important to re-seal the bag after every use to keep any moisture out.