I've completed your survey.
Could I ask if any of your group actively keep aquariums?
I ask because experienced hobbyists aren't normally hung up on water parameters etc. Marine aquariums are going to be a bit different to freshwater, but freshwater aquariums tend to just stay stable when established and constant monitoring just isn't necessary.
While these monitoring systems are a thing, especially in marine aquariums, they aren't commonly used and unless it was comparable with the cost of a good test kit I don't think it would be marketable. It would be an interesting engineering exercise, but these things are already on the market but arent in general use. You arent going to spend 100s on a monitoring syetem for aquariums that you dont have 1000s invested in when a £30 test kit does the job. In marine aquariums you can link these automatic monitors to dosing mechanisms so that correct mineral content can be maintained etc. They have benefit there. Marine aquariums are way more expensive, they have elements that can be automated, there are more parameters that need monitoring and sumps where you hide away intrusive bits of kit, so it makes more sense to do some kind of automatic monitoring.
I think a question as to whether the respondents are freshwater or marine would be useful.
The only time that monitoring would be done on any kind of frequent basis on a freshwater aquarium would be when first setting up an aquarium and the cycle is establishing.
