I know it is a big no-no to mix coolant due to silicates falling out of suspension and clogging things up. I'm running coolant, I think it is Zerex, that has the Cat EC-1 rating. I lost a little during some maintenance and I can't seem to find that brand in the local stores anymore. Can I top it off with another brand coolant if it is also EC-1? I have some Peak Final Charge sitting on a shelf. My understanding is that the EC-1 rating means there are no silicates to start with, so I feel like that wouldn't be a concern. Just want to be sure.