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Close Sidebar - X Click On Any Question Below to Get an Answer Without Leaving the Page Have questions, comments or suggestions? Contact me at: admin@substratecalculator.info Will Not Answer Mushroom Cultivation Questions! Substrate Preparation Questions Q : How Much Gypsum Do I Use in a Bulk Mushroom Substrate? A : You can use five to ten percent gypsum in your bulk substrate, measured by volume, to see increased yields & performance. : You can use five to ten percent gypsum in your bulk substrate, measured by volume, to see increased yields & performance. This is in addition to the gypsum you should be adding to your grains during their soak (if that's how you prepare your grains). Click Here to Hide Answer Q : How Much Coffee Grounds Do I Use in a Bulk Mushroom Substrate? A : You can use ten to fifteen percent spent coffee grounds in your bulk substrate for increased yields & performance. : You can use ten to fifteen percentcoffeein your bulk substrate for increased yields & performance. On a side note, you can also use half strength brewed coffee water as the soak water for your grains, instead of plain water alone, to see increased colonization times for your grains. Click Here to Hide Answer Q : What are Some Good Bulk Mushroom Substrate Additives? A : Things like chicken manure, gypsum, coffee grounds & worm castings are all great additives. However, only when the proper amounts are used, otherwise, you'll do more harm than good. : Things like chicken manure, gypsum, coffee grounds & worm castings are all great additives. However, only when the proper amounts are used, otherwise, you'll do more harm than good. Gypsum is a great additive that supports the very healthy development of mushrooms, as it provides a much needed source of sulfur and calcium. Gypsum should be used at around five to ten percent by volume. Chicken manure should never be used at more than five percent by volume. The reason for this is because it's too "hot" (nitrogen rich) & will burn the mycelium. Coffee grounds can be used at around ten to fifteen percent by volume. Worm castings can be used at around ten percent by volume. More could be used without doing any harm, but their texture is like that of dense mud when they're hydrated, making them unsuitable as anything more than a carefully measured & used additive. Here is an excellent thread at Shroomery to read about Mushroom Substrate Additives that goes into great detail about each and every one. Click Here to Hide Answer Q : Should I Pasteurize or Sterilize My Bulk Mushroom Substrate (or neither)? A : You should always pasteurize your substrate & not sterilize it. The reason for this is because you won't be innoculating your bulk substrate in sterile conditions like you would if you were doing, say, the PF Tek. You pasteurize a substrate by holding it at 140 degrees Fahrenheit to 160 degrees Fahrenheit for at least 90 minutes. : You should always pasteurize your substrate & not sterilize it. The reason for this is because you won't be innoculating your bulk substrate in sterile conditions like you would if you were doing, say, the PF Tek. You pasteurize a substrate by holding it at 140 degrees Fahrenheit to 160 degrees Fahrenheit for at least 90 minutes. By only pasteurizing & not sterilizing your bulk substrate, you allow a select group of microorganisms to survive the pasteurization process. These microorganisms in your substrate won't harm or inhibit the mycelium you'll be spawning to it, but they do inhibit the growth of molds & other bacteria that may land on your bulk substrate when you're spawning to it. Pasteurization also ensures that you kill all mold spores, seedlings & most bacteria & other harmful organisms that would otherwise prevent the mushroom mycelium from properly colonizing your substrate. If you were to sterilize your bulk substrate prior to innoculation, if some mold spore or bacteria were to land on your substrate during the innoculation process (and they most surely will), they will thrive in an environment with no biological competition for the nutrients in your substrate (since molds/bacteria grow at a significantly faster rate than mycelium, the mycelium doesn't actually count as competition until it has fully colonized a substrate. When mycelium as fully colonized a substrate, it is all but 100% protected from contamination). Click Here to Hide Answer Q : How Do I Properly Pasteurize My Bulk Mushroom Substrate? A : Pasteurizing your bulk substrate might seem like an intimidating idea at first, but it is actually quite easy. : Pasteurizing your bulk substrate might seem like an intimidating idea at first, but it is actually quite easy. You pasteurize your substrate by holding it at a steady internal temperature of 140 to 160 degrees Fahrenheight for a period of at least 90 minutes (temperature measurement should be measured at the core/center of the substrate). There are a number of methods to do this, such as placing your substrate in quart jars and placing those jars in a "hot water bath" or by placing your substrate in oven bags and then placing those bags in a "hot water bath". Here are a couple of excellent threads at the Shroomery that give step-by-step instructions on how to pasteurize your bulk substrate (which should always be performed, particularly if you want to use any additives that will increase the performance of your substrate): Proper Pasteurization of Substrates (in oven bags) Proper Pasteurization of Substrates (in quart jars) Proper Pasteurization of Substrates (in oven bags, but with dry heat) Proper Pasteurization of Substrates (for MASS Amounts of Substrate) There are plenty of other threads outlining how to pasteurize your bulk substrate, those are just some "fan favorites" and are well laid out (both in words & with pictures). Feel free to search for more if none of those suit you. Click Here to Hide Answer Q : How Much Coir/Verm/Poo Do I Use in a Bulk Mushroom Substrate? A : This is kind of a grey area. One of the most infamous monotub teks ( : This is kind of a grey area. One of the most infamous monotub teks ( Damion5050's Coir Tek ) uses a "recipe" that is 80% coir & 20% vermiculite (by volume). You'll see others have use 30% horse or cow manure, 30% vermiculite & 40% coir. Others have used straight horse manure with great success. Others still have used 70% coir, 10% verm, 10% coffee grounds, 10% horse manure. There is no "magic recipe", so feel free to experiment. The most important things you want to make sure you've got nailed down when you've got your final mix ready to go are: Texture Moisture Level You want a nice, light & fluffy texture to your bulk substrate. It shouldn't muddy or clumpy, as this leads to slow/incomplete colonization. You also want to make sure you haven't over or under saturated your substrate. The perfect moisture level for a bulk substrate is called "field capacity". Click Here to Hide Answer Q : How "Wet" Should My Prepared Bulk Mushroom Substrate Be? A : Your substrate should have enough moisture added to it to bring it to what is referred to as "field capacity". Field capacity is a term used by mushroom growers (amongst other professions) to refer to the perfect amount of moisture in a given substrate. : Your substrate should have enough moisture added to it to bring it to what is referred to as "field capacity". Field capacity is a term used by mushroom growers (amongst other professions) to refer to the perfect amount of moisture in a given substrate. To get a rough idea of field capacity, it's about what a wrung out sponge feels like. If you can pick up a handful of your substrate and hold it in your hand and no water drips from it, then you can squeeze that same handful of substrate kind of hard and only get a couple droplets of water & then lastly, squeeze that same handful of substrate really hard and get a small stream of water for a second or two and then it stops, that's about field capacity. Here is an excellent video on YouTube demonstrating how to check your substrate for field capacity. Click Here to Hide Answer Help decide what content goes here!! Visit the Shroomery thread about this site and leave your comments, suggestions or questions. Alternatively, you can email me at: admin@substratecalculator.info Help decide what content goes here!! Visit the Shroomery thread about this site and leave your comments, suggestions or questions. Alternatively, you can email me at: admin@substratecalculator.info

Click on the bulk substrate container shape below that you plan on mixing & fruiting your final bulk substrate in.



If you have a round tupperware type container or jar that you want to use, click the "round" button. If you have a "tote bin" type container that is square or rectangular, click the "square/rectangular" button.



Please note that you can't use an oval shaped container and expect the "round" calculator to work.

This refers to what the desired total volume of your final mixed & "ready to fruit" substrate will be.



So lets say you have an odd shaped container or a container that you've used before, and you know that it takes 3 total quarts (spawn + substrate) to get it to the level you want it in that container. Then you would enter 3 quarts below.



Please enter only one of the three "known volumes" below.

If you know how many pints of total combined substrate you want (spawn + sub) please enter it here.

If you know how many quarts of total combined substrate you want (spawn + sub) please enter it here.

If you know how many gallons of total combined substrate you want (spawn + sub) please enter it here.

If you know how many liters of total combined substrate you want (spawn + sub) please enter it here.

This is where you'll be entering the information about the size of your bulk substrate container (length and width or radius) as well as how deep you want the substrate to be in that container.

This refers to the radius of the container you plan on using to make your bulk substrate in. The "radius" is defined as the distance from the center of the bottom of your container to the outside edge of the container. You can use whole numbers as well decimal numbers.

This refers to the width of the container you plan on using to make your bulk substrate in. You can use whole numbers as well decimal numbers.

This refers to the length of the container you plan on using to make your bulk substrate in. You can use whole numbers as well decimal numbers.

This refers to how deep you want your finished bulk substrate to be. You can use whole numbers as well decimal numbers.

This refers to the ratio of spawn to substrate that you want to use.



So, for instance, if you wanted the final mixed substrate (all of your bulk ingredients and spawn together) to consist of 25% spawn and 75% bulk ingredients, you would enter a spawn ratio of 1-to-3 here which would mean for every 3 parts bulk substrate, there is one additional part spawn.



You can use whole numbers as well decimal numbers.

The numbers you'll be entering below refer to what percentage of each ingredient you want your bulk substrate to be made of.



The definition of a bulk substrate is what you add spawn to, so enter the percentages without taking how much spawn you have into account.



So, for instance, if you wanted your bulk substrate to be straight coir, you would enter 100 in the Coco Coir field. If you wanted your bulk substrate to be eighty percent coir and twenty percent vermiculite, you would enter those numbers in their respective fields.

Here is where you'll see the total combined volume of bulk substrate & spawn needed to give you a final mixed bulk substrate that will meet the criteria you entered on the left (width, length and depth of the final "ready to fruit" substrate).



You'll have that total volume returned to you in three units of measure (pints, quarts & gallons) for convenience.

Here you can see what percentage of your final mixed "ready to fruit" substrate will be spawn and what percentage will be your bulk ingredients. This is here simply to help clarify the "Spawn Ratio" you entered to the left.

This is what you've been waiting for! Everything you need to make the final mixed substrate you want, in the container you want and at the depth you want it, is below!



All you have to do is make sure you've got enough spawn (and if you don't, you could always try a lower spawn ratio or a smaller container or even reduce the depth of the substrate).



Once you have the amount of spawn shown to you below, then all you have to do is mix up the other amounts of the ingredients below, pasteurize the mixture, wait until it cools & then add your spawn!



If you measure each of the ingredients below correctly so you have the amounts shown, when you finally put the complete mixture into the container you entered the dimensions for, it will be the depth you entered above.

Please Select Your Preferred Unit of Measure: U.S. Standard: Metric:

Please Select Your Bulk Substrate Container Shape: (on the following page, you can mouseover any red question mark to clarify something you don't understand...try it:)

Revisit/Save/Share Your Results Using This URL Simply copy or bookmark the ENTIRE URL below and revisit it to have your input & results automatically populated. You can also share this URL with others to share your results and "recipe"!

Required Inputs for Calculation: (green fields are required) Container & Substrate Size Information: Container Length: inches Container Width: inches Desired Substrate Depth: inches Desired Spawn Ratio: (spawn-to-sub) Ratio of 1-to- How Full Are Your Spawn Jars? 2/3 3/4 Full Substrate Will Be Made of What % of the Following Ingredients: (Gypsum will not be added to the running total as it is considered a "non-volume adding" ingredient) Coco Coir: Percent Vermiculite: Percent Coffee Grounds: Percent Gypsum: Percent Hay or Straw: Percent Sawdust: Percent Horse Manure: Percent Cow Manure: Percent Chicken Manure: Percent Worm Castings: Percent Other: Percent Current Total: 0 Percent Your Results: (after you've filled in the input fields click the calculate button on the left) Total Substrate Volume In: Pints: 0 Quarts: 0 Gallons: 0 The Final Mixed Substrate Will be 0 % Spawn & 0 % Bulk Ingredients You'll Need a Total of 0 Quart Jars of Spawn & 0 Quarts of Pasteurized Bulk Substrate Volume Required of Each Individual Substrate Component In: Spawn: Coco Coir: Vermiculite: Coffee Grounds: Gypsum: Hay or Straw: Sawdust: Horse Manure: Cow Manure: Chicken Manure: Worm Castings: Other: Pints: 0 0 0 0 0 0 0 0 0 0 0 0 Quarts: 0 0 0 0 0 0 0 0 0 0 0 0 Gallons: 0 0 0 0 0 0 0 0 0 0 0 0