FML: Shutting down

[gregzz4]

Really sorry to be reading about all your losses lately Pat
Since your Mandy is still swimming, I'm probably wrong but ...

If I recall correctly, this started right after you set up your dosers, yes ?
Have you checked into possible contamination from your dosing products and/or equipment ?
Also, have you tested for copper ?
And a long shot, but is your RO still removing all chlorine (or chloramines if your municipality uses it ) ?

Hope you figure out the cause