I just don't understand why none of the test tubes are 5ml?? Some tubes are even marked at different heights?
Does anyone know why? I don't think I'll be buying API anymore, they fill to about 4.5-5.1ml??
I've only noticed it cause some of the lines came off and I place them side by side when filling. I guess the lines came off with me boiling the tubes after each use, don't need none of that in my tank.
From now on I'm using a syringe to fill the tubes, that way ill know I'm using 5ml of water