DIY peristaltic pump

Has anyone here worked on a DIY peristaltic pump? I am looking to make the mods and pump below. Thought I would check before going through it. If not, but you have a commercial unit, have you had any problems dosing phyto?

http://www.home.zonnet.nl...r_pmp/index_doseer.htm

This mod turns the 24 hr timer into a ~ 40 min timer

http://youtu.be/xGfV9IUcFxE

Attached Image(s)

I did a DIY unit with a few parts from ebay
 
Pump $12.98
http://www.ebay.com.au/it...mp;hash=item51c9eefd9c
 
Relay $2.19
http://www.ebay.com.au/sc...RM+PIC+AVR&_sop=15
 
Arduino $3.88
http://www.ebay.com.au/it...mp;hash=item3f37dffa10
 
Clock $1.22
http://www.ebay.com.au/it...mp;hash=item3f3a685c2e
 
Some parts I had laying around (Power packs and wire).
 
I then have a small sketch to run the pumps as needed based on time from the clock.
I use two feeds per rotifer bucket so that if I have a failure, on one, they still get a feed.
 
Overall for 4 rotifer buckets the cost was
Pump $12.98 * 8
Relay $2.19 * 4
Arduino $3.88 * 2 (I also added an LCD and buttons to manually feed, but this was me being fancy).
Clock $1.22 * 2
Power packs, cables, solder etc $20
 
Total $142.80 for eight pumps plus some time, so an average per pump $17.85.
Each Arduino is attached to four pumps, one to each rotifer bucket.
Each bucket has two feed pumps
I can expand with up to 14 pumps per arduino from memory without having to change the hardware much.
 
I used two pumps as I was making it all and wanted to ensure it was as reliable as possible.
As it happens, none have failed so far and they have been running for about 3 months now.
I probably could have used 1/2 the equipment.
 
Total cost for just 1 pump
Pump $12.98, Relay $2.19, Arduino $3.88, Clock $1.22, Power pack and cables $10
Total $30.27
 
The entire lot sits inside a fridge.  The pumps are attached to a piece of acrylic that they sit on, then feed from containers of algae stored in the fridge (again 2 containers).
 
regards

Darren

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That's a pretty cool setup. I have been wanting to play with an Arduino, this might push me over the edge to actually do it. I plan to try the one above still though since I have all the parts in my parts boxes. I am thinking I can run multiple lines on a single physical "timer".