looking at chiller for rdwc, help needed with maths!!!!

Hi, as title says im looking at doing my first rdwc been doing loads of reading old threads and stuff and see that chillers can be a sound investment, due to space i am looking at 5-6 site in 20litre pots brain/control pot and res, the chiller thats been offered to me is a aqua one polar bear with a min 100 gph, and max 400gph, i believe its 1/3 hp, my querie is how do i work out if that chiller is to big or too small, im sure this is a total newb question that has been hit on time over but i really cant get my head around it, so if anyone can help id apreciate it, at least id get some sleep!!!
cheers
coz

1/4 hp capable of chilling 170 gal. And a 1/10hp=93gal.

It's fine, it just means the chiller won't have to work very hard cooling your 30 gallons.
The info you really need to know about with a chiller is "minimum flow requirements"
My 1/4hp chiller will cool 70 gallons 35 degrees and up to 170 gallons 10 degrees. It requires a 900gph pump minimum 1200gph max, to push the water through the chiller. I bought a 950gph danner mag inline pump to meet my needs
If you need a pump this big make sure the return lines to your rdwc are large enough to handle the flow

UnderCurrentDWC said:

It's fine, it just means the chiller won't have to work very hard cooling your 30 gallons.
The info you really need to know about with a chiller is "minimum flow requirements"
My 1/4hp chiller will cool 70 gallons 35 degrees and up to 170 gallons 10 degrees. It requires a 900gph pump minimum 1200gph max, to push the water through the chiller. I bought a 950gph danner mag inline pump to meet my needs
If you need a pump this big make sure the return lines to your rdwc are large enough to handle the flow

Click to expand...

hi, thanks for your time, i get what your saying i think, i was planning 19mm (3/4) pipe work, the min is 100 gph and ill be looking for a good pump to match, i was worried that id have to pump too hard to match the 100gph and end up with too much flow in buckets, trying to find out the best amount of bucket changes per hour are? as this is my first dwc i am sure ill be getting things wrong but just trying to get prepared, and reading lots of posts (and youve been involved in a lot of them) im getting there, little tips like the danner inline just make it all easier, my theroy is if the chiller doesent have to work too hard it might last longer!! so a good pump to match is just as important cheers again cozz

With flow requirements of 100-400gph it sounds like you have a chiller smaller than 1/3hp, I'd say 1/10hp but I could be wrong.

hi, heres the write up Features:

The required flow rate through the chiller is between 100 gph and 400 gph. When sizing a pump keep in mind that aquarium chillers will add approx. six feet of head pressure.
15 degree cooling up to 125
1/4 HP
Dimensions: 11-3/4" Tall X 12-3/4" Wide X 15-3/4" Front to Back
The controller can be set as low as 56F
Adjustable temperature controller. Constant digital temperature read-out
Titanium heat exchanger
The R134 refrigerate meets all environmental and international guidelines
Adjustable temperature controller
Thermal protected compressor
its a polar bear cc-50 chiller, im sure it means more to you then me, as im still trying to work out how it has a hp even though theres no pump!!!lol, but yeah i think ill go for it