It has been a while , but i have finally gotten around to work on the pump control problems i previously had and here is the result.
It turns out the pumps really run way better on 12v, control is still being done via Tip120s (with heatsink this time) , although they do not really get as warm as i previously experienced.
For now it is running in semi autonomous mode : you can switch the pumps on/off via a small Python program i wrote (also used for monitoring), but they also shut of automatically once the desired level is reached (electrodes you can see going into the bottles)
There is also a small 5v fan which is only controlled manually for now , but which will be automated as well (on/off switching based on temperature)
Next step will be led lighting control , which will be quite a bit trickier , since it will need manage a large number of leds, with different channels (red/blue), and will need to be modular aswell (thinking of smaller sized led arrays that can be linked together )
The python and arduino programs are pretty messy for now, so a lot of work will go into that area as well
Remote control, and dataloging is also planned /partially implemented
Here are a few videos of the (messy) prototype:
Hydroduino prototype : working pump control vid 2 from mark "ckaos" on Vimeo.