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Digital Reality
Strangers in the dark


Registered: 05/01/07
Posts: 187
Last seen: 8 years, 1 month
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Question About Petri Dishes
#8218381 - 03/31/08 07:17 AM (15 years, 10 months ago) |
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Ok so i guess my question is pretty much how do you guys that do agar work keep you dishes sterile. Or get them that way i should say. I use the plastic disposable ones and was told when i bought them from myco supply that you could pressure cook them. Well thats not the case because i cooked them after i poured my agar for 25Min's at 15psi and they twisted and distorted and spilled agar all over the place. So i tired again the next day by just pouring sterile agar into the dishes in a glove box. I had taken the dishes and soaked them in a bleach solution for an hour or so. But about 2 days later i have weird looking gell stuff in the dishes. So i don't know if its from the bleach mixing with the agar or a contam. Id think its a contam becuase i did rinse them in hot water after so the bleach should have been gone.
So yeah, do you guys just use them as they are and have not problems or do you sterilize them somehow. Maybe boil them? i dunno.
Thanks, Keith
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Prisoner#1
Even Dumber ThanAdvertized!


Registered: 01/22/03
Posts: 193,665
Loc: Pvt. Pubfag NutSuck
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the plastic dishes should come sterile, sounds like you have polystyrene dishes, cant autoclave them, they may have believed they sent you polymethylpentene or polypropylene dishes, those can be autoclaved. you can sterilize the polystyrene dishes by cleaning with bleach and an alcohol rinse, using water can lead to contamination
agar is supposed to 'solidify' into a gel, if there's any unusual growth it's probably contaminated, toss it and start over
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Digital Reality
Strangers in the dark


Registered: 05/01/07
Posts: 187
Last seen: 8 years, 1 month
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Re: Question About Petri Dishes [Re: Prisoner#1]
#8218410 - 03/31/08 07:50 AM (15 years, 10 months ago) |
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yeah i know it turns into a gel. this is something extra that def wasn't there to start with. i guess ill just give it a go by wiping them out inside the glove box with alcohol. Do you know of where i can get some of the disposable dishes that can be used in the cooker? Any info would be great
Thanks, Keith
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HybridprX
Biodegrader of coir



Registered: 01/29/08
Posts: 2,588
Loc: Canada
Last seen: 6 years, 5 months
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They sterilize the plastic petri dishes with UV gamma lights (kills spores/bacteria) without pc'ing.
They are intended to be 100% sterile right out of the pack.
You just need to sterilize your agar mix in the PC at 15psi for 45 minutes then place in the glovebox with your dishes and poor, seal, let cool and then your ready for use.
No pc'ing the "disposable" petri dishes
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Prisoner#1
Even Dumber ThanAdvertized!


Registered: 01/22/03
Posts: 193,665
Loc: Pvt. Pubfag NutSuck
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Quote:
Digital Reality said: Do you know of where i can get some of the disposable dishes that can be used in the cooker? Any info would be great
you can find the polymethylpentene usually listed as polycarbonate or the polypropylene, both can be steam sterilized but both are considerably more expensive because they're reusable. disposables are cheap but the only methods for sterilization is through the use of chemicals or gamma radiation, if you want a gamma sterilizer look under beauty supplies
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Digital Reality
Strangers in the dark


Registered: 05/01/07
Posts: 187
Last seen: 8 years, 1 month
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Re: Question About Petri Dishes [Re: Prisoner#1]
#8218679 - 03/31/08 09:57 AM (15 years, 10 months ago) |
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Thanks guys. I guess ill give it another go in a day or two when i have a few more shrooms shoot up to clone. Third times a charm i hope.
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tahoe
Noob Slayer



Registered: 11/26/03
Posts: 6,274
Loc: N38.93829W119.98108
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Re: Question About Petri Dishes [Re: HybridprX]
#8218832 - 03/31/08 10:51 AM (15 years, 10 months ago) |
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Quote:
HybridprX said:
You just need to sterilize your agar mix in the PC at 15psi for 45 minutes
Pr0_X would suggest that you do three cycles of 15psi for 45 mins 2 days apart. After 6 days your agar will be ready.
-------------------- Stop experimenting half way through your first grow. Grow it to maturity, watch it, learn from it. Do this a few times then experiment with different ideas and figure out what works best for you.
My Legacy https://www.shroomery.org/forums/showflat.php/Number/22140987#22140987 Teh=The I need to proofread
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Digital Reality
Strangers in the dark


Registered: 05/01/07
Posts: 187
Last seen: 8 years, 1 month
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Re: Question About Petri Dishes [Re: tahoe]
#8219056 - 03/31/08 11:47 AM (15 years, 10 months ago) |
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lol what... did i miss something. im guessing thats a joke, and aside from that i thought you wanted to keep your times down to 20-30 mins so you don't caramelize the sugar. Or am i wrong?
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HybridprX
Biodegrader of coir



Registered: 01/29/08
Posts: 2,588
Loc: Canada
Last seen: 6 years, 5 months
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I use PDA for agar, but from what I read most people PC for 30-45 minutes at 15psi.
I've PC'd pda for 45 minutes at 15psi, let the pressure drop, remove the beer bottle and poor inside a glovebox into 120ml mason jars. Had some nice TX isolates going that I let go to shit from in proper storage.
Trust but 30 minutes should be just as good as 45, call it caution.
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Edited by HybridprX (03/31/08 11:58 AM)
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tahoe
Noob Slayer



Registered: 11/26/03
Posts: 6,274
Loc: N38.93829W119.98108
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I find the agar is good at 20-30 mins at 15psi. The whole caramelizing thing is blown way out of of proportion.
RR like using a lot of water in the pc when cooking agar. Make the water level=with the agar level. This way the pc cools slowly, very slowly and doesn't suck in a bunch of air.
His procedure is very valid but i do not worry about it.
I stuff the opening of the flask with polyfill and allow it to cool for the majority of time in the pc, about 45 mins. If its still to hot I will leave the lid 1/2 way on the pc to cool a little more. When its about 15 mins from pouring I put it in the glove box with the petris and spray the glove box with alcohol. I pour once its very cool. Usually the last petri that I pour is all lumpy because the agar has solidified in the flask
-------------------- Stop experimenting half way through your first grow. Grow it to maturity, watch it, learn from it. Do this a few times then experiment with different ideas and figure out what works best for you.
My Legacy https://www.shroomery.org/forums/showflat.php/Number/22140987#22140987 Teh=The I need to proofread
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Peterthinks
(Caulking) gun for hire


Registered: 11/10/04
Posts: 2,379
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Re: Question About Petri Dishes [Re: tahoe]
#8219121 - 03/31/08 12:05 PM (15 years, 10 months ago) |
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I've got a few hundred polypropylene 50 MM dishes I melt my pre made agar in the microwave put 1 teaspoon of agar in the dish (PDA agar) then cook them 15 mins at 15 psi. After the cooker cools I take em out and tape them up. So far several clones are happily growing in my laundry room I had some contams but I blame my dirty open air counter top transfers, not the dishes or agar they stay clean for weeks till I mess with them. Any contamed ones go back in the cooker to kill then dumped and re used. Sleeve of 20 for $25 The only place I could find them was a medical lab supply house.I had to buy hundreds so I didn't feel so raped on the shipping.but I've actually been using the same 20 over and over. I'll mail you a sample if you're seriously interested in a couple sleeves and want to try one out.
20 is enough to clone with, you take 5 samples and take the best looking sectors into 10 dishes, clean out the first 5 and you have 10 to isolate those sectors into if you still need more transfers. It's straight to grain or liquid culture after that point. PM me if you're interested I know they're kinda pricey but it's cheaper than glass and they don't break
-------------------- Give a man a fire and he will be warm for the rest of the night. Set a man on fire and he will be warm for the rest of his life. NEWB NEWBIE NEWCOMER IGNORANT? QUESTIONS? Click HERE HERE HERE HERE For detailed instructions with pictures on how to grow mushrooms. There is a lot of info on the Shroomery and this is what you need to know.
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Brainiac
Rogue Scientist



Registered: 04/29/06
Posts: 13,259
Loc: 與您的女朋
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Re: Question About Petri Dishes [Re: Peterthinks]
#8219137 - 03/31/08 12:08 PM (15 years, 10 months ago) |
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I've heard of people using brown cardboard instead of agar in Mycalium running...
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Fair is Fair
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Peterthinks
(Caulking) gun for hire


Registered: 11/10/04
Posts: 2,379
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Re: Question About Petri Dishes [Re: Brainiac]
#8220699 - 03/31/08 05:37 PM (15 years, 10 months ago) |
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Yes, cardboard works. If you'd like to try PDA I got a recipe below. I've never met a mushroom that didn't like it. With cardboard you'd be restricted to saprophytes.... Uhhh... Wood eating shrooms like Cubes. Well if you get into gourmet mushroom you may find it useful. -------snip----------------------------- (Cooking measures for PDA agar) I have access to a scale but got sick of borrowing it to measure this. 1 Liter water 300 G potatoes 17-20 G Agar 2 G Brewers Yeast 10 G Dextrose Here are cooking measures that make the same measurements. Put 3 cups of water in a 4 cup measuring cup. Cut up one large red potato(unpeeled)and push the chunks into the water till it reads 4 cups. pour it in a pot. Add 1 more cup of water so your 1 cup of potatoes are being boiled in 4 Cups of water. Boil for an hour and drain. Keep the water,eat the potatoes. Add water to bring up the level to 4 and 3/4 Cups. The following are LEVEL measures... Drag the back of a knife over a heaped measuring spoon to make it flat. 2 Tablespoons + 1 Teaspoon of Agar 3/4 Teaspoon (1/2+1/4)Brewers Yeast 1 Tablespoon +1 Teaspoon of Dextrose mix the dry. Heat the potato water in the microwave or on the stove till hot again. Mix the dry ingredients together then add the dry to the water while stirring. Pour it sterilize it and use it. -------------------snip--------------- Check into BRF agar substitute too. It's a paste of brown rice flour and water that you can use instead of agar. good luck sir
-------------------- Give a man a fire and he will be warm for the rest of the night. Set a man on fire and he will be warm for the rest of his life. NEWB NEWBIE NEWCOMER IGNORANT? QUESTIONS? Click HERE HERE HERE HERE For detailed instructions with pictures on how to grow mushrooms. There is a lot of info on the Shroomery and this is what you need to know.
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Brainiac
Rogue Scientist



Registered: 04/29/06
Posts: 13,259
Loc: 與您的女朋
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Re: Question About Petri Dishes [Re: Peterthinks]
#8220729 - 03/31/08 05:42 PM (15 years, 10 months ago) |
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Cubes just love it.Theres not very much, they don't like.... I buy a mixed from FP..
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