I have emailed them regarding this. It took a long time to get a response but this is a cut and paste of their response to me.
"Sorry that is has taken us so long to get back to you.
The axis on the light metre graph are showing the following: X – Axis is for the nanometre value, the Y- Axis is the percentage of the light that is being read.
Regarding the screen shot you have sent through, it appears that there is a bug with that particular graph as it should be showing you a graph on the right hand side at every point you click on the graphic. We have forwarded this to our Developer for further investigation."
After not hearing back from them I contacted Bulk Reef Supply to see if they could help. They contacted Seneye who then responded back to me with this reply. (Again, cut and pasted.)
"Apologies for the late response. We have forwarded your query to our engineering team. This is the first time someone has enquired regarding the accuracy of our light meter.
We will have to double check regarding your query, please bear in mind that we will be closed over the Christmas period, but will try to get back to you at the beginning of January."
On January 9th I sent Seneye another email asking "Anything new yet?" I know they get the emails because there is an automatic reply email from them stating so. But I have yet to receive any replies back.
So I'm left wondering, did I stumble across a known deficiency in their meter or did I just get a faulty meter? This is why I am asking if anyone else can duplicate this situation. If it is a known deficiency, can it be fixed with an update? If it is a faulty meter, can it be replaced? Just ignoring a paying customer in hopes that they will go away is a pretty sad way of doing business.