1. The biochemistry uses both integer arithmetic, and discrete time steps of 0.2 seconds. Rounding down often makes the decay from 255->0 quicker than you would expect looking at the decay from 255->127 (which would otherwise be a true half-life).
2. The Science Kit graphs are only drawn accurate to the pixel, so when the concentration on the graph there appears to be at its minimum, it may not have actually reached it. If you try and measure exact times of decay in the Science Kit, you won't get as accurate results as here.
3. If you hex-edit a gene file, and change the decay rate to values other than in this table, you will just get the same behaviour as the nearest lower value in the table. For example, any value from 0 to 7 will behave as 0 does, and any value from 64-71 will behave the same as 64.
| Decay number (the "half life" in the genetics kit) | Time to decay from full concentration to half (255->127) | Time to decay from full concentration to none (255->0) |
| 0 | 0.2 secs | 0.2 secs |
| 8 | 0.2 secs | 0.8 secs |
| 16 | 0.2 secs | 1.4 secs |
| 24 | 0.4 secs | 2.6 secs |
| 32 | 0.8 secs | 4.4 secs |
| 40 | 1.4 secs | 7.6 secs |
| 48 | 2.6 secs | 12.4 secs |
| 56 | 5.0 secs | 19.8 secs |
| 64 | 9.8 secs | 39.4 secs |
| 72 | 19.8 secs | 1 mins 19 secs |
| 80 | 39.8 secs | 2 mins 38 secs |
| 88 | 1 mins 20 secs | 5 mins 17 secs |
| 96 | 2 mins 40 secs | 10 mins 33 secs |
| 104 | 5 mins 20 secs | 21 mins 7 secs |
| 112 | 10 mins 40 secs | 42 mins 14 secs |
| 120 | 21 mins 20 secs | 1 hours 24 mins |
| 128 | 42 mins 40 secs | 2 hours 48 mins |
| 136 | 1 hours 25 mins | 5 hours 37 mins |
| 144 | 2 hours 50 mins | 11 hours 15 mins |
| 152 | 5 hours 41 mins | 22 hours 31 mins |
| 160 | 11 hours 22 mins | 1 days 21 hours |
| 168 | 22 hours 45 mins | 3 days 18 hours |
| 176 | 1 days 21 hours | 7 days 12 hours |
| 184 | 3 days 19 hours | 15 days 0 hours |
| 192 | 7 days 14 hours | 30 days 0 hours |
| 200 | 15 days 4 hours | 60 days 1 hours |
| 208 | 30 days 8 hours | 120 days 3 hours |
| 216 | 60 days 16 hours | 240 days 7 hours |
| 224 | 121 days 8 hours | 1 years 115 days |
| 232 | 242 days 17 hours | 2 years 231 days |
| 240 | 1 years 120 days | 5 years 97 days |
| 248 | 13 years 226 days | Absolutely ages |