We've been cold-brooding chicks now for a while, working out the best ways to help chicks stay warm on their own while we brood them in the house. After spending all we had that we COULD spend on chicks in the spring, we wanted to try to hatch some eggs. Having no obliging hens - they all refused to go broody including our bantams who seem to have had every useful trait bred out in the pursuit of pretty - we needed an incubator. Being persistently financially challenged, our only option was to build one.
A fish tank that I had acquired second hand, which had a crack in the bottom panel, served as containment. A 30 gallon model with thick glass, it would hold heat reasonably well. Kevin prepared it by laying down a layer of newspaper to protect the glass, and then putting about an inch and a half of fine gravel in the bottom (from a leftover bag labeled Tube Sand which wasn't QUITE sand!). A $7, 40 watt ceramic bulb heater, a $10 clamp lamp with an extension cord and a $5 thermometer were the only expenses, nickeled and dimed out of bits of income here and there.
We wrapped the tank in reflective bubble insulation that we had leftover from another project (the cold brooder huddle box, actually). We covered the top with two more pieces of insulation (with boards on top to hold them flat) and another piece of board since we had no more insulation. I put some triangular blocks in to use as risers, and we used the bottom half of 18 pack egg cartons to hold the eggs - the risers elevated one side. Flip them 180 degrees twice a day to rotate the eggs. We put in a bowl of water also to help with humidity.
Fired it up, to see how warm it would get. 90 degrees. We then wrapped the tank in a layer of cardboard on top of the insulation. That raised it another 7 degrees. Right on the edge of what we needed. I decided to try it anyway since we were unsure of the accuracy of the thermometer, but none of the eggs hatched.
We wrapped it in another layer of cardboard, which brought the temp up again, JUST to 100 degrees, and from that we had two chicks hatch, but neither one survived (they simply did not learn to eat - I've seen that in turkeys, but this was a first in chicks). I think that the hatch failures this time may have been because we had no place to store the eggs that was cool enough to prevent germination from starting, and the only place I could store them was getting quite warm about once a day. This can cause germination to start, then die.
During the warm months when we were experimenting with this, the temperature was adjusted by moving one of the cover pieces - the cover had three panels so we only had to open up one piece at a time and not cool the whole thing at once. So I'd just leave a little gap between two of them to lower the temp a bit.
The incubator was on the basement floor, so the temperature stayed pretty even throughout the day. The upstairs got pretty hot, but the basement stayed cooler, and once we got the temp in the incubator stabilized, I only had to adjust the covers to vent a bit if it got up over 101, or close them up if it got below 98. The adjustment was actually pretty fussy, a tiny difference could make a difference of 2-3 degrees in the incubator. I finally set it so that the open gap was V shaped. It was easier to just adjust one side of the vent. The vent gap varied between 1/4", and 1/2" on the wide side. It was that sensitive.
We decided to give it another try, feeling that somehow or other we just HAD to make this work, but fall had settled in, and temps were lower in the incubator as we went on, and I couldn't think of a way to raise the heat at the time. We had two more hatch, but they failed to thrive also, in part because of indications of low humidity.
Not wanting to give up, I put more eggs in, and threw a thick towel across the top. That worked for a day or two, but temps dropped a little again, and I put a heavier cover on it, but that was too hot! I ended up leaving the blanket on two panels of the top cover, and then regulating with a gap again. I also started misting the eggs once a day.
I did not save the eggs upstairs this time, instead I took them down as soon as I had a carton filled.
We now have chicks hatching out. Two have hatched successfully from the first carton we brought down (temperature adjustments were not very accurate during the first few days), and so far four from the second carton. I think our fertility in the eggs is probably low due to the two randy roos that we had to dispatch (they were too small to reach the hens, in spite of vigorous and continuous attempts, but had sequestered about two thirds of the hens and kept them from the older roo). The fertility on the third carton should be better since we acquired another roo who knows his job but does not wear out the hens.
Anyway, we seem to have finally got the formula right for successfully hatching eggs from a VERY low tech homemade incubator. No thermostat, no humidity meter, nothing more than a heat lamp, thermometer, and spray bottle.
It has been kind of discouraging up until this point, but the three chicks in the mini-brooder, and the three hatching downstairs give us great hope.
We set up a mini-brooder which is small so it contains the body heat of tiny chicks, and it has a short huddle box for tiny chicks, so they go right from the incubator to the mini-brooder (as soon as they dry out and are standing), then into the regular cold brooder at about a week of age. So far we have the mini-brooder sitting on top of the food dehydrator, to give it a warmer spot (not much warmer, maybe 80 degrees), because we do not want to lose this first batch, and the first few days are the tricky ones with cold brooding (when the mama usually has them mostly under her).
If you have a home incubator, you do have losses. Eggs that never germinate, eggs that never hatch. Chicks that hatch but fail to thrive. Chicks that thrive, and then die unexpectedly. These things happen, and we have to deal with it. Sometimes a chick won't ever walk. Those are the worst. They inevitably die, in spite of anything you can do. You just watch them linger for days before they finally stop cheeping and breathing. That is the part I hate. The little noisy fluffies in the brooder do help make up for it though, and make it worth doing again.
More experiments to come, when we are more confident of our incubator.
UPDATE: We ended up with six chicks, two of whom did not survive. The other four are now out in the coop with the grown-ups, dodging pecks from the dominant hens and the guineas, dashing in and out faster than the older hens can run. They are thriving, having gone out at about 9 weeks, fully feathered out and two of them obviously roos, one uncertain, the other definitely a hen. The two randy roos did manage to get at least one good hit in, because one of the chicks is definitely male, definitely half Fayoumi, started crowing at 4 weeks of age. If he can regulate his urges better than his papa, he may just get to replace one of the old roosters. Otherwise, he will make fantastic soup!
NOTE: Cold brooding refers to brooding WITHOUT a heat lamp. It may include brooding in the summer only when temps in the house or in a contained area outside are high, or use of a pre-existing heat source in the house such as a woodstove, radiator, or heater vent for the first few days, but where the temperature is typically NOT 95 degrees to start, but much lower.
We use a plastic bin, with a layer of newspaper covered in about 1" of sand, gravel, or dirt (depending on what we have). If we use sand or gravel, we toss some dirt in also, to expose them to the microbes from the dirt - helps give them natural probiotics and some pathogens that they build resistance to (this reduces risks of various soil-borne illnesses). They scratch in the dirt or gravel, and pick up grit naturally this way, and we just scatter feed on top of the brooder floor (this is how we feed our chickens outside also, scattering their feed, we use no feed dishes except for things that are very liquid). They scratch around, wiggling their little fluffy butts, looking like toddlers playing grown-up. Very cute. Sometimes I use chopped dried herbs to give them greens in tiny bits, and since they run under whatever is being dropped, they end up getting seasoned instead of getting fed! I break mealworms for the first few days only, then feed them whole, and tossing in a couple of pinches of those just gets them chasing each other for the tasty bits.
A huddle box is a box that has had one side cut out, and turned upside down. Usually a pretty small box, just tall enough for the baby chicks to run into - ours was 7X7X7 to start, and then we cut it to be only about 5" high. The box contains their body heat, and they use it instinctively. We line the inside with reflective bubble insulation, to provide a little additional radiant warmth. Gotta make it small, this size will hold a dozen chicks, or even 15 or so, they group together under it. If you make it very big, it fails to hold the heat, and it is nearly impossible to fit it into a plastic bin or brooder box without it taking up too much of their space - they'll be tripping over the waterer trying to get out of it if it is too big.
We use a mini-brooder with a short huddle box for chicks just out of the incubator. Once they are three to five days old (the age you'd usually get them if you ordered them), we move them to a larger brooder with a huddle box that is a bit taller (about 1" higher).
We use the huddle box continuously in the mini-brooder, and for the first 3-5 days in the standard brooder. After that, we use it only at night for another week, and then the huddle box is taken out completely. We also leave them near the heater vent only for the first week in the big brooder, and then move it about 6 ft away. We move the brooder each week, to successively cooler locations, ending at about 4-5 weeks on the enclosed back porch, then we move them out in the daytime, and in at night for a week, or two, depending on temps and feathering stage (we put them out in the coop when they are fully feathered - they go as a group, and have learned to huddle together for warmth).
This time, we have chicks hatching over a period of a week, so we are going by the age of the youngest chicks to make changes in brooder conditions.
We have learned that groups of more than 12-15 chicks do not do well cold-brooded - they may have issues with piling and the ones on the bottom will smother. We divide up larger groups into multiple brooders. We have also learned that when you put turkeys in with chicks, the chicks may crawl under the turkeys when the turkeys are standing and the turkeys will sort of settle down as they get sleepy, and can crush the chicks if you have very many turkeys in with the chicks. Sad, because chicks can teach turkeys to eat, and some turkeys won't learn to eat without something to show them. Putting bantams, or quail, in with turkeys would be a really bad idea, for this reason. It is also not a good idea to leave large depressions in the floor of the brooder if you are using sand or gravel. When you put it in, smooth it out clear to the edges so there is not a drop off in a corner, because the chicks may huddle in the depression, and others are more likely to crawl on top of them - smothering again.
Cold brooding has been a success here, though there have been some learning experiences, and some losses because of it. But I'd not go back to a lamp - no way. The chicks are just so much more vigorous and active, and they are hardier, and there is a lower risk of fire when you do not use a heater.