Ok, sad morning so far

[Rbishop]

Not to mention the fact that cardinals and cory are not the easiest fish to handle tank swaps...

 

[KarlTh]

I see TDS testers online (and can see having one in the future because I want to have a nanotank one day), are there any other "hardness" tests available to check the before and after water at the tap ?.

Bog standard GH and KH testers. However, they're very misleading about water that's been through a domestic softener because they don't flag up the high sodium and chloride levels.

 

[Hooked Newbie]

Ok, so the coral has been pulled from the tank and I did a 30% water change as well. Panda's are pissed I took away their hiding spot but otherwise everybody is doing ok. Thank you for the feedback and now I will have to come up with another scaping idea.
I'm not sure of the details for the softener but given the location of the "pre softener tap" using it instead of the tap is next to impossible.
I see TDS testers online (and can see having one in the future because I want to have a nanotank one day), are there any other "hardness" tests available to check the before and after water at the tap ?.

I just picked up a digital TDS tester this weekend. I was actually very surprised at how affordable it was ($15 at the LFS). I'm sure it's not "top of the line", but it works for my needs. I got it primarily to test my RO water, but I'll also definitely be checking out my FW tanks.

Sorry about the fish losses.