Well, here is the data (yawn) from my most recent run with the bators I do hope that it may be of some use to others in TV land! I don't know how to import a table into the forum and i don't have excel anyway, so i have to sort of make a table.................. Eggs set into two Brinsea Octagon 20 Eco incubators the evening of 21 November. Hatch date would be =/- 12 December. 44 eggs set. Each unit had 22 eggs. ALL AMBIENT DATA IS FROM ACCURITE INSTRUMENTS ALL INCUBATOR TEMPS. DAYS ONE TO EIGHTEEN ARE FROM THE GLASS THERMOMETER INCLUDED WITH UNITS. ALL INCUBATOR RH READINGS ARE FROM ACCURITE INSTRUMENTS. DATA, DAYS ONE TO SEVEN: Avg. Ambient Temp.: 71.9 Avg. Ambient RH: 32.8 Avg. Temp. Unit I: 99.4 Avg. RH Unit I: 42.7 Avg. Temp. Unit II: 101 Avg. RH Unit II: 41.9 Candling day seven eliminated two clear eggs and one blood ring. Now down to 41 eggs: Unit I with 20; Unit II with 21. DATA, DAYS EIGHT TO FOURTEEN: Avg. Ambient Temp.: 72.2 Avg. Ambient RH: 34.5 Avg. Temp. Unit I: 99.5 Avg. RH, Unit I: 41.5 Avg. Temp. Unit II: 100.4 Avg. RH Unit II: 38.8 Candling day 14: one more odd looking clear removed. Now down to 40 eggs: Unit I with 19; Unit II with 21. DATA, DAYS FIFTEEN TO SEVENTEEN: Avg. Ambient Temp.: 72.4 Avg. Ambient RH: 41.4 Avg. Temp. Unit I: 100.1 Avg. RH, Unit I: 44.5 Avg. Temp. Unit II: 100.4 Avg. RH, Unit II: 37.1 Candling day 17 made it clear to me that at least some of the eggs would not hatch, some air cells quite small, embryo odd shaped, egg not lost enough weight, etc. Nevertheless, forty into lockdown. DATA, DAYS EIGHTEEN TO TWENTY-ONE: Hatching Unit is a Hovabator Genesis 1588 Bator temp and RH is recorded by Accurite instrument. Avg. Ambient Temp.: 70.9 Avg. Ambient RH: 28.7 Avg. Hatcher Temp. (by Accurite): 99.3 Avg. Hatcher RH (by same Accurite): 77.6 RESULTS: As I suspected early on, hatching began a bit early. First egg hatched at noon, day 20 hatch complete by same time day 21. 36 eggs out of 40 hatched: 18 out of each unit. Three of the eggs I had doubts about did not, in fact, hatch. The fourth, well...............c'est la vie. 90% hatch. Very pleased.