CUBLOC aquarium controller

So I know that there are several options out there for aquarium controllers, but they are all a little pricey dont you think? as well as being limited. I thought that it woudl be fairly easy to build my own. I have been looking at the CUBLOC units that use ladder logic to program them. You can add practically anything to these units and program them to do anything you want. such a "push button water changes" set it to turn off sump returns, open a valve to release set amount of water, close valve, refilt same amount of fresh water back in.
Has anybody else tried tinkering with these to control their aquarium?
Id like to know how you faired.

 

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It sounds great ! There is one problem. Even if Your Aquarium-CPU will be cheap, all the sensors: pH,nitrate,oxygen,red-ox electrodes are damn expensive. These are not DIY projects... Unfortunately ...

Any suggestions ...?! The idea is great! Though still will be bl***y expensive!

Cheers!

 

I have a Omron Zen which is a Nano logic PLC that I was messing around with to turn lights on and off plus do some other stuff. They are pretty cheap with the unit only costing about $124.00. This leads to endless possibilites that you can do with your tank, the only thing is you need to understand logic code and be good with wiring. ;D