Water in a Mother Flask

[RoyalOrchids]

How much water or other liquid overlays is too much in a mother flask? The mother flasks are baby food jars with about 30 ml of medium. There is about 2 mm of sterile, distilled water on top of the seed in one flask. I used more water to get the last of the seed from my test tube, and wound up with about 2 cm of liquid on top of the media in flask #2. They are not vented, so I can't count on evaporation.

Anybody deal with this? What is the most water, disinfectant, nutrient overlay, or other liquid that anybody has been successful with?

[newflasker]

A thin layer of water is OK but 2cm is too much. You could get what it's called glass Chateaux on the sand. Kidding, it's vitrification: leaves look beautiful, glass-like but seedlings will not grow anymore. Use a syringe and suck water out.

[RoyalOrchids]

I'll do that. I knew I could count on you, newflasker.

[RoyalOrchids]

How much would be too much? (in mm)

[John D.]

2 mm is probably OK, 2 cm is almost 3/4 inch. and is probably way too much. The water will come to equilibrium with the chemicals in the medium but not disolve the agar. Some people sow in liquid media which is the same chemical formula without the agar anyway. Also many people use 80 - 90% of full strength media and have better luck at germinating.

[RoyalOrchids]

John D.

Thanks for the response. Your explanation makes sense. I was worried about the water having a diluting effect. You put my mind at ease. Now if you could just make them hurry up and GROW!

[tuteca]

Hi!!!
I have to say that my experience is very poor, but I observed than a thin layer of water on the medium surface rises the appearing of protocorms, with respect to the 'dry' ones. They grow faster... Someone with a good explanation for??

[RoyalOrchids]

I figured I'd post an update.

I definitely had too much water/sterilant in there. I removed most with a dropper. They grew just fine and are in replate flasks now. Thanks for all the help!