1. **How can we Monitor the growth of a Colony?**
   As detailed in [[E-coli#**Experiment**|E-coli]], we could use an LED and a light sensor and detect how much of the light is going through, which shows us how much is obstructed by the bacteria. The Problem with this approach is that dead bacteria look the same as alive ones. Another approach would be detecting the Produced gases, and while this could work, it is very likely to be inaccurate. This is why monitoring the population growth is **not an optimal approach** in our case. The population stops growing at a certain height anyways, at least if we dont use a **heater**.


2. **How can we monitor the current size of our colony?**
   Using the approach documented in [[Bacillus Subtilis#**Experiment**|Bacillus Subtilis]], we could use SYTO 9 pigment, which usually has a quantum yield of <0.01, which means that the brightness of the pigment when excited by blue light is less than 1% of the light. However, if the pigment binds to DNA or RNA, its quantum yield rises to around 0.4, which means the brighness is 40% the brightness of the excitation light, which is pretty bright. If the bacteria dies, its dna is destroyed in a few minutes. Once this happens, the quantum yield of the pigment decreses again. A camera (ESP-CAM module) can be observing the petri dish from above, and a blue light filter could be used to increase the contrast between the non populated area and the colony. Ideally the Experiment would be sealed inside a dark room with only the fluorescence light illuminating it. Finally, we could use a heater to make the conditions for the bacteria less harsh. **This is the optimal approach from our current point of view.** However, ever dye has pros and cons, which is why we dont have to use SYTO 9 but maybe something like fluorescein.