If you add a little water wetter to the mix it will restore the lost cooling power due to the antifreeze.The Mix I am using now is 6 parts distiled water 3 parts antifreeze and 1 part water wetter this is for ambient temp water cooling. For my super cooling rig I have to use a lot more antifreeze
I am useing a 50/50 mix of antifreeze and well water it does a good job for me. The type of antifreeze I am useing is Siera which is the new type that isn't glycol. It is friendly to the little animals. Glycol if an animal drinks it it will kill them. Siera will not make them sick.
water wetter is an anti corrosive in itself , running both anti freeze and water wetter is kinda redundant ,also I think most brands suggest a 50/50 mixture ,but you really only need 15-20% polyglycol to prevent corrosion
I have dissimilar metals in my system, both alluminum and copper and I didn't make this system to use it as a battery so thats the reason for antifreeze+distilled water and water wetter it gives me a higher content of corosion inhibitors in the mix and also distilled water does not conduct so I feel safe with this setup. Also antifreeze does not cool as good as water so if you have antifreeze in your mix you should add some water wetter as it resores the lost cooling power.