New resin tank versus old ones

Yesterday I got my Form1 back from upgrading.
First I tried to print with an ‘old’ clear resin tank (it was defintively a brand new one) -> but nothing was cured to the buildplatform, even lowering about 0.7 mms. Then I took the new (orange) tank and after lowering Z by 0.2 mm it worked…
Does anybody knew why the old ones don’t work any more ?

Peter - older resin tanks should still work so that is very strange. It could have been a defective resin tank. You can shoot us a message and we can help replace it if necessary.