Making a T.I.T. incubator - Need a bigger incubator? read this.

[sheepherder]

I'm posting this thread because i think some of you might find it (TIT "tub in tub" incubator) as useful as i have over the years.

I initially learned how to make one of these on a Mycology forum, and i would never bother w/ any other diy incubator.

Good reasons to try a TIT..
1) inexpensive to make
2) very little temp fluctuation (once dialed in)
3) way roomier than your typical store bought incubator
4)EVEN internal temp of every inch of use-able space.
5)good humidity level
6)use-able for "anything" that needs incubating.

The concept is simple yet very effective.
top tub sits inside bottom tub that is filled with heated water. Top tub becomes your incubation chamber.

supplies list
1) (2) rubbermaid, sterillite, etc.. storage bins of the same make and size.
2) medium quality aquarium heater (the kind that has adjustable temp control on top)
3) something to use as spacers between tubs. ie. a couple bricks, 4 small coffee mugs etc..
4)plastic zip tie's ( 10in. or so)
5)digital thermometer w/ probe (the 6-10 dollar type)

optional supplies... to make things easier.
1) digital thermometer w/ water-proof probe (typically used for aquariums and very inexpensive)
2)temp controller of your choosing (hydrofarm, activeaqua reservoir controller, etc.)
3)lg towel or sm blanket (for winter if your ambient temps are too cold)

Step 1.
Place tub in desired location and put your spacers in tub.
You could just use a couple of clean bricks, one on each side, but i find it works better if you have something in all 4 corners. I use 4 small coffee mugs, all the same kind and size to keep things level.
All these are for is to create a 3 or 4in. space between the floor of the tubs. This keeps the weight of whatever goes in the top tub, from crushing/sitting on aquarium heater.
This would be a good time to mention this.
If you can, try and buy one of the heaters that have a hard plastic or metal shell. In my experience (iv'e tried them all) they work much better than the glass ones do.

Step 2.
place heater in the bottom of the tub. if your not going to use the temp controller, manually set the temp on the heater for 3 or 4 degrees higher than your target temp your incubating at. This is to compensate for the heat having to go through the plastic floor of the top tub. If your going to use the controller its not a problem because you can set it externally afterwards. It's not necessary, but use the suction cup and harness it comes with and stick it to the floor of the tub. It may come off over time but that is no problem. it just keeps it stationary, where you put it.
I place mine on either end and run up the closest inside corner with the cord.

Step 3.
Put the second tub into the tub w/ heater and spacers.

Step 4.
Now your going to want to zip-tie the 4 corners together until there snug.
If you can, try to find the storage containers that already have holes in the rim on all 4 corners and the center of both sides.
That way you don't have to drill your own holes in the rims of the tubs.
Zip-tie the middle of both sides of the tubs as well until snug. Try and tighten them down evenly.
The reason you have to zip-tie the top tub down now, is because if not, as soon as you fill the lower tub with water it will push the top tub up from the water pressure. It would be very difficult to zip-tie after its filled with water. Trust me i learned the hard way. lol
see pic below.

 

[sheepherder]

Step 5.
Now it's time to fill the bottom tub with water unti it's an inch or two from the top. It helps if you stick your finger of the hand your not poreing with in-between the tubs, so you can feel when it's almost full. That way you dont overfill it and get water all over the floor, "speaking from experience" lol.
I use a funnel and gallon milk jug to do this. it makes things easier.
Another thing that makes things easier is to start with water that is aprox. the same temp as your target incubation temp. it levels of and dials in much quicker that way.
If you chose to get a waterproof probe therm., push the probe down into the water, in-between the two tubs.
This will let you keep tabs on the water temps so you know the heater is functioning properly, and it gives you something to compare the controller temp to, which never hurts.
Your water temp will have to be about 3 or 4 degrees warmer than target temp because it has to go through the plastic of the top tub.
Example.
if your target temp is 82f, then your water temp will be aprox. 85f

 

[sheepherder]

Step 6.
Plug your heater into your chosen controller, set it for proper incubation temps, and,......Voila. You have a very stable, dependable incubator.

Like i said, the temp controller is optional but if you need to adjust the heater temps manually, you have to cut the ties, adjust the temp, then zip tie it back down again. Only this time you have to deal with the water pressure, adjusting each tie a little at a time until its all the way down.
So yeah, save yourself the trouble and spend $35-40 bucks on a controller that can be externally adjusted.

Another thing that you'll want to do is get a fluted ceiling tile from home depot like the one in the pic, and put it inside your incubator, on top of 4 shot glasses in the corners.
That way your incubation containers are not sitting directly on the floor of the tub. The air inside the incubator will be your set temp, but if put directly on floor it will be warmer because the heated water is in direct contact with inner tub.

Place the probe for your digital thermometer inside your incubator. Now you know exactly what the internal temps are at a glance. I also hang a small analog therm. from a suction cup on the underside of the lid, and stick the probe to the backside of the therm. That way it's suspended and not touching anywhere in direct contact with heated water.
See pics..

Step 7.
This one is VERY IMPORTANT!
Because there is nothing to aerate/circulate the water in the bottom tub, you MUST add salt to the water.
As long as you put salt in the water it cannot grow bacteria and become stagnant.
Even though the water never comes in contact with the contents inside the upper tub, you still dont want nasty water beneath it.
I use 2Tbsp. salt per gallon or two of water. You could probably use less but i like to make sure.

Once a week, check your water level and make sure to keep it topped off. You want the heated water on all sides of the tub, not just the bottom.

It sounds like a big pain in the arse, but trust me. This is a great alternative to the small incubators on the market and it holds temp very well and consistent.

You can also fit a ton of egg containers in one of these because you can use storage containers(tubs) as big as you need to.
Thanks for reading this, hopefully someone will find it useful.

Oh, i almost forgot..
If your house is cold in the winter, it helps to put a towel or small blanket over the lid to keep the warmth in a little better. It acts as a layer of insulation.

 

[Terrain_pull up]

Nice. It definitely takes the styrofoam cooler with water in the bottom to another level which is how I started out. I like the idea of making it as big or small as required as well. I still make all my own incubators but have since moved to what I call "dry" incubators..lol..just using heat tape. I'm still using coolers though

 

[indyana]

Nice! This is a really great tutorial for the DIY fiend. Thanks a bunch for all the pictures as well.

 

[sheepherder]

Nice. It definitely takes the styrofoam cooler with water in the bottom to another level which is how I started out. I like the idea of making it as big or small as required as well. I still make all my own incubators but have since moved to what I call "dry" incubators..lol..just using heat tape. I'm still using coolers though

Yeah, this way the water is just used as the catalyst for the heat source. No chance of whatever is in the incubator ever coming into contact with the water, and because its surrounded by water on all sides but the top, you get nice even temp through the available area.
It works amazingly well. Better than one might think. It's also no big deal to put together. It can be built in less than an hour, closer to a half hour then very little maintenance.
I actually have a cabinet style incubator i used to use with a heatbomb "heater in a bottle silicone off".
Now i use it with a thermostat and heat tape, for insect breeding. Superworm pupa mainly.
I prefer the TIT...hands down.

 

[sheepherder]

Nice! This is a really great tutorial for the DIY fiend. Thanks a bunch for all the pictures as well.

Thank you.
Just thought i'd share what works for me and countless others in different avenue's.
It's not a new method by any means, but its tried and true.
If it helps out even 1 person on here, than it was worth taking the time to do.
Thanks again!