Updates and progress have been slow to come. I spent tank time this weekend working on parts for my surge valves; assembling and vapor polishing printed parts. No photos of these for now, as I would like to post the complete valve build at once. So we will just have to wait on that.
The other thing I did over the weekend was clean up a few bugs in my light controller code and validate the performance. I have another thread with the build and files for the controller (
here's the link). All links in it are the most current versions, including the code. But I'll throw my test data up here as it seems as good of place as any.
I took a PAR sensor and datalogger and got some measurements from my setup. Treat these as qualitative; they were not made with any rhyme or reason to the sensor placement and there was no controlling for ambient light in the room. I hope to find some time in the near future to measure spectral distribution and light uniformity from the fixtures. But it hasn't happened yet.
In any case here is a diel curve of PPFD from running the lights on Sunday. The x-axis is in minutes from start of logging as I neglected to check to see that the logger clock was set to local time before starting measurements (rookie mistake). In any case it paints a pretty clear picture of how the dimming performs.
There are two step changes in intensity at the start and end of the curve. At the start, these correspond to the blue LEDs coming on and then the white. At the end its the reverse. These appear to represent the minimum on intensity using the default MarsAqua drivers; using my dimming circuit and the default pot-dimmer I get the same minimum. So no room for improvements there without putting different drivers in the fixture and that is out of scope for now.
Here is the test setup for those that are interest (I didn't hold the logger all day, just for the pic). You can see the sensor in the background sitting on the rock work. Its roughly in the middle of the tank vertically and off center of the LED fixture.
