Best Water Temps? + Do It Yourself Water Chiller Details!

DolfBegins said:

I'm attempting to put together a version of this design, would you mind posting a layout drawing of flow/parts ? I've seen some people put the pump in the res, using it to push the water out, but are you placing a second pump after the cooler to pump it back or has that seemed to be strong enough? I'm expecting to need to expand this cooling ability but haven't run a first test yet. Waiting on tubing.

Thanks!

Click to expand...

You should only need one pump. Its best practice to use an external pump where possible to reduce heat in the res and leave more room for the roots to grow without disruption.

plebschmo said:

You should only need one pump. Its best practice to use an external pump where possible to reduce heat in the res and leave more room for the roots to grow without disruption.

Click to expand...

Thanks for your response, in the end I just could not find a pump that can handle the requirements that doesn't require being submersed.

My build:

Serpentz said:

Alright, right now I got my temp controller set at 20c. For water temp, that feels quite cold to me. I'm not quite sure how my DIY chiller will work out, but so far, so good.

Click to expand...

If you search on "oxygen absorption vs water temperature", the graphs that you'll get show a pretty gentle curve so, from an absorption perspective, there doesn't appear to be an "optimal" value. My water chiller is set for 20°C and I'm thinking I based that on the amount of O2 that would be dissolved + being a level when O2 is well absorbed by the roots + a level that will tend to inhibit "bad things" (scientific term) from growing.

"feels quite cold" - no doubt!

have you figured out how much heat you are extracting per watt using the Pelletier coolers? would be a cool metric to know.

I know this is an older thread but I am going to try this out and can’t quite figure the wiring. I am using the same components suggested by OP:
PC power supply for 12V DC supply
STC-3000 Temperature controller
Water pump
Pre-built thermoelectric cooling block

Those last three components all run on 12V DC.

I’m unsure how the 12V rail on the PSU should connect to the inputs on the other three components, and how the cooling output of the controller should connect to the pump and cooling block.

The controller runs off 12V (diagram is wrong in there) but seems to not output 12V, is it meant to actually power the pump and cooler or only switch them on and off? If powering them is it just passing through the same 12V supply it gets from the PSU?