ucdwc pump question

Im wondering why everyone uses such large pumps for ucdwc, i have a small external 290 gph pump and it seems to circulate the water just fine between 8 5 gallon buckets.
I do have larger pumps quite a few actually but is there any benefit to running a larger pump? my buckets have an air stone in each and i have a sunleaves dura pump 560 8 way out for air so i have plenty of o2 running through my water.
the surface tension of the water is broken in each bucket by the flow but its certainly not like the action you get from havin a huge mag drive pump hooked up.

To me it seems as though running a big pump would just raise water temps faster and as mine stay right at 63 with no chiller so id like to avoid adding unnecessary heat unless its absolutely necessary.

I dont know the answer to the question.

But, with respect to your last sentence about a chiller, you *will* need one -- once plants get bigger the temps start to go up more in the Under Currents.....

Good luckw ith your grow, post up some pics!

ive got a chiller sitting around from an old reef tank, dont see any reason to run it though all its gonna do is cost me extra money running a pump all the time i dont need. My water temps have never gone above 69 running the same pump im using now but with half the water volume so with the extra water volume so the temps will be even lower now. the temp in my room only varies by 2 degrees so its not gonna get any hotter even during the peak of summer.
i will shoot a few pics when its all squared away its a little ghetto fabulous right now because im just testing for leaks and water volume/level. when i clean it up and run all the air lines properly i will post a few pics.

no one wants to pipe up on this?

an you were right kitty had to have my chiller hooked up ran it for three days without an my temps climbed to 72. i think its the air pump putting heat into the water more than the recirc pump though.

Just an fyi if anyone is looking into getting a chiller i highly suggest the aqua logic line, ive had my ds3 for 15 years it sat outside for at least 3 years after i took down my reef tank, brought it in dusted it off an its working like a champ again. plus with the external controller i dont run the pump for the chiller all the time like you have to with the units with the built in temp readers, only when the chiller is working is the pump on. so much more efficient.

What deadband range does everyone run for their chillers? I have it set to kick on if the water reaches 69 an cool to 65.
should i set the deadband tighter or is a 4 degree temp swing ok?

There's very, very, very few UnderCurrent grows currently being showed off here............. Perhaps start a grow journal and be the star of the show?! ANd on the chiller, sucks you had to use it but glad you were prepared. Most people get dead plants before they get a chiller installed. Good luck dude!

Stoneyk said:

Im wondering why everyone uses such large pumps for ucdwc,

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I use a 950gph pump to meet my chiller flow requirements.

Stoneyk said:

What deadband range does everyone run for their chillers? I have it set to kick on if the water reaches 69 an cool to 65.
should i set the deadband tighter or is a 4 degree temp swing ok?

Click to expand...

My chiller is set @ 64* and kicks on @ +3*, so +4* sounds fine.

Stoneyk said:

Im wondering why everyone uses such large pumps for ucdwc, i have a small external 290 gph pump and it seems to circulate the water just fine between 8 5 gallon buckets. To me it seems as though running a big pump would just raise water temps faster and as mine stay right at 63 with no chiller so id like to avoid adding unnecessary heat unless its absolutely necessary.

Click to expand...

I was wondering this myself. I was considering using smaller pvc pipe between each bucket with a small pump connected to the return manifold. I think the real question is how many times per hour is it neccesary to recirculate the system. With airstones in each bucket and the pump spilling into the resevoir, a smaller pump should work. But I am no expert.

I tried the smaller pvc an wouldnt suggest it, the levels dont stay correct in the buckets even with a small pump. 1 1/4 is the only way to roll or even go bigger but thats as big as i wanted to go in a round bucket. plus this leaves room for your system to grow by adding more buckets an a larger pump to flow them.