Phaethon said:

There are still lots of things that can go wrong in a still air box, which can't be ruled out from your description. They mostly involve either agitating the air or hovering non-sterile things (like hands or scalpel handles) over open plates. Leaving plates open instead of lifting lids exactly long enough to take or place a wedge also increases your risk.

It's possible there were mold spores on top of the culture on the germination plate (e.g. from hovering hands over an open plate, or a failed wrapping that started letting in non-sterile air). Those would have trouble germinating on existing mycelium but no trouble at all when transferred to sterile media.

Wispy mycelium is common for germination and even a transfer or two afterwards. If you're still using water agar for the transfers, that will definitely cause wispy growth too - use 1.5-2% malt extract or BRF or whatever you have, and save water agar for cleaning up bacterial culture (or just go straight to BRF pucks in that case). And a pinch (0.2%) of baker's yeast or nutritional yeast in the agar media helps cultures fill out a bit better, at the expense of some sediment in your plates.

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Yeah true about the technique but I think I've gotten better even since before this spore print. The mold grew on multiple plates exactly from where the specks of spores were on every plate so I don't think it was from the air.

But check these, they are extremely thin and whispy and transparent. It's almost hard to see it. These are transfers from water agar to 1% MEA.


And this is from the plate that three out of four transfers got mold. Moved the only one that didn't have mold to another plate.
It's also very thin and whispy with some growth in the air on the left side there but not at all dense.



I was thinking 1% might be too low so I'm making 2% now, just finished pressure cooking, waiting for it to cool down. Will make some transfers from the plate with four pieces on but is there any point in making transfers from these when they are so thin? Can it get thicker/stronger when isolating?

LewDoja said:

💯

Water agar is for bacteria anyways.  Which could also be accomplished by higher agar% most bacteria will have hard time on 3% (which is excessive)


Also grabbing plates with fingers on top/bottom flexes the plastic and acts like a diaphragm. (Another reason I ziplock plates (snack bag)).

Myc will definitely grow through agar (i.e. hot pour/sandwiched tek).

Soo many possibilities it's kind of fun to conjure up the "what ifs"

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LewDoja said:

What is your agar %?

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