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Beetle Substrate Guide

Lets make this as easy as possible

Here are the very basics: in regards to US native species, Dynastes tityus and granti, Strategus aloeus and antaeus, Gymnetis thula and any Cotinis species, Osmoderma species and Euphoria species can be raised on "Organic Raised Bed Soil" alone! If a larger size is desired, simply mix in raw sawdust! This will be explained in the next slide. But without any mixtures, the organic soil alone will achieve average sized adult beetles!

Mixing the Organic Raised Bed Soil

Say goodbye to hard to make flake soil!

So if you decide to go down the dark path of ditching flake soil once and for all, but still want that sweet large major male, know that it is still very doable, and easy! Mix in 3/10th of the substrate mass in raw sawdust, you can use any of the hardwood grilling pellets consisting of Oak or Mesquite wood. I personally opt for Mesquite as it is the most affordable option. Make sure the sawdust expands and stir it with the "Organic Raised Bed Soil" throughly. Leave the mixture for two weeks, and stir it whenever you remember to do so (doesn't have to be often). Once the two weeks is up, it is ready for you to add beetles! 

A few words of caution:

A. make sure the organic soil you use do not compose of cow manure. Cow manure contains a bacteria that can cause leg rot with a lot of beetle larvae species and can kill your larvae quickly. That said, most "Organic Raised Bed Soil" purchased from Walmart or Home Depot does not contain cow manure and can be used without issues.

B. This substrate mix is not meant for: any US Lucanid (stag beetles), and any of them Phileurus or Hemiphileurus species.

C. If the intent is to raise large cetoniids (flower beetles), adding a large portion of rotting leaves will also yield desirable results, although raw sawdust works perfectly fine.

Making Flake Soil

You gotta do it sometime

You really don't have to stress about making flake soil - things ferment in the wild all without human intervention after all. But sometimes, we just gotta speed it up!


How to Make Flake Soil

Can't be that hard can it?

First up - if you leave raw sawdust by itself in a moist state long enough, certain lucanids will eat it. Yes, you heard me right, the more hardy species will do just fine on aged sawdust. But this might cost you 6 months - a year's time.

So, how do you make flake soil?

Well, you will need ingredients first. 20lbs of hardwood grilling pellets of just about any brand will do the trick for the wood part, but oak and mesquite are your best choices. Then, you need to add 5lbs of unbleached flour, and some dry yeast.

The first step is to pour out and expand the pellets with water, and then turn it into sawdust. Warm water works best with this step, but cold will do just fine.

Then you pour the flour into the expanded pellets, along with a table spoon of yeast. You want to mix throughly here, so there isn't huge clumps of flour - an occasional small piece here and there is fine. 

The end result should be damp, but not wet. You can check it by squeezing the substrate. It should form a clump and not fall apart when released, all the while having no water come out. If you made it too wet, leave it in somewhere sunny for a few days and stir more often, you will be fine.

Now the waiting game begins. In this stage, you want to mix up the substrate at least once in 2 days (once a day is better). You should notice the substrate heating up, if it does not heat up, simply add more yeast.

It will be about 3 weeks to a month before the soil is ready. Be sure to wait till the substrate is fully cooled down. 

Yay, now you have flake soil! The rest of beetle keeping will be a breeze!


Raising the Larvae

You have the substrate so this is sooo easy!

How do you raise the larvae then?
Most dynastid larvae are communal, so it could be as easy as putting a bunch of them together in a 5 gallon tub. Do note that you have to change out the substrate once a month (or more often depending on the size and number of larvae).
Most Lucanid larvae are not communal, at least with regards to US natives. They can be housed in a 16 cup filled to the brim with flake soil. 4 small holes is enough for ventilation. Simply change the substrate once a month, and your beetle will be adult in no time! (I lied, probably 6 months to 1 year depending on species).



You raise up the larvae! Yay!
Now, this is the easy part! If you leave the larvae in the substrate it is raised in, they will form a pupal cell, and come out as an adult in 2 months. You don't have to do anything! Normally, you can see a ring of darkened substrate around the larvae, signaling a cell.
But what is you dug it up?
Well, an artificial cell is easy to make. Simply buy some floral foam (Walmart has them!), and carve out a pupal cell. It should be just wider than the pupae and twice as long. I like to cover it with moist paper towels so it holds moisture better. Put the cell in a dark, poorly ventilated area, and you're set!

Keeping the Adults

Just don't flip them over...

Okay, so now you have substrate and you raised up the larvae, hurray. 
First, adults have a hibernation period, when regarding captive raised beetles. This could be 2 weeks to most of a year, depending on species. In this period, the adult do not feed. I keep track of this by putting them in deep moist substate, and leaving a layer of paper towels on the surface. When the paper is torn, the adult is active.
Keeping most scarab and Lucanid adults are easy, simply remember to feed them jelly or fruit. Though one thing you must remember: BEETLES ARE STUPID!
They tend to flip over a lot, and you must prevent this. They can die in just a few hours flipped over. To prevent the issue, simply layer the surface with bark and thick tree branches, the more the better, or lay down a one inch layer of hardwood mulch.


Breeding the Adults

In a Nutshell

Breeding beetles can be one of the harder parts of beetle rearing - 
Some Lucanids, like Dorcus, needs logs for breeding, if it is not provided, few or no eggs will be produced.
But in general - most lucanids will happily lay eggs in 7 inches of substrate. I like to put every species in a 5 gallon bin, and simply check for eggs every month.
The same goes for Dynastids, but for most species, organic raised bed soil can be used!
Organic raised bed soil can work for Cetoniids as well, but some species like some hardwood leaves on the surface, so be sure to provide that when required. 
I will try to make various blogs on niche species that does not follow this trend.

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