You should never let untreated greywater pool or be accessible on the surface of the ground; it should soak into the soil and irrigate plant roots. Even if you add chlorine it will not be a suitable or healthy quality of water to be in a pool or be accessible to people. There are treatment systems that remove nutrients and nullify potential pathogens in greywater, but those systems are quite costly and you’d be better off spending the money on increased efficiency in the home or other systems (like rainwater collection).

Sounds like you may want an alternate water source to fill a pool? If so, look to rainwater, condensate water, or other cleaner sources. Not greywater!

Thank you very much appreaciated, and I do have JO-JO  containers for rain water. I now only need the rain.