DIY Cold Air Intake for Air Pumps

[ocgreen]

I am struggling with 5 gallon bucket reservoir temps and considering a cheap DIY solution:

Running a 1/2" hose from the intake for each of my 950 GPH air pumps to the inside of a beer fridge freezer. The thought is that I could drill a 1/2" hole for each intake hose and seal with silicon or expanding foam as needed. The hose would pull cold air from freezer to attached air stones, and logically I feel like this should drop temps by a few degrees.

Anyone tried something like this? I see some DIY options where you put a couple hundred feet of hose in a freezer/fridge and the water cools as it travels through; I'm looking for a simpler approach.

Anyone think of any health/safety issues with above idea?

Thanks for taking the time to read my post.

(I know that using a larger tote helps stabilize temp, ph, etc. I'm also looking at building a little cover/shade for my buckets which would reduce amount of light hitting them.)

[PRIMO]

You would need to punch an intake hole on the other side of the freezer, if this works for you great! As long as the beer stays cold.

[maner]

Nice idea, in this last month i was trying to figure out how to put my air pump outside of the window so i can bring the cold air directly to resevoir but the idea of long connection hoses from air pump to airstones may cause a problem prevent me to do so. Cause the air pump which im using lowers the air pressure in time and i turn it of by turning the on/off wheel and after i press more on off side it makes some noise like the release of the pressure and when i turn it back up it continues working like brand new wit a lot of bubles in water.

can u add pictures of the system

peace

[ocgreen]

I haven't built this yet. I was just doing some brainstorming and thought of drilling into a mini fridge/freezer combo I can pick up for less than $50.

[Toker1]

That’s is an inefficient way to chill the water. Your heat pump will be working harder than what work actually goes into cooling the water. In other words, you will be spending more on electricity than what is needed to get the job done properly. Why not get an actual water chiller? I believe you will save $$ in the long run (when considering operational costs) if you invest in one.

[RagWeedDWC]

Toker1 I think you may have sent me that link a while ago, and it works. Just need the area you have the chiller in, cooler than your grow area. For a fact though it will decrease temps, but it has limits.

[Toker1]

Yes, agreed... when temps get over 85F. My little chiller 72w has a tough time. Luckily for me that rarely happens. That’s why I suggested the 100w model.
And yes... almost forgot (great post below) the clear tube sucks. Be prepared to blacken it out or replace with a black one.

[ocgreen]

Thanks guys. You both gave me a lot of good info to consider. Think I may pick just one up to see how it works and go from there.

[RagWeedDWC]

I have tested this in the past, pulling air from my keg cooler fridge. What I found is the volume of air moving through the pump from the fridge was not enough to overcome the heat generated by the pump. There was a modest decrease of temp coming out of the pump, but not sufficient to cool the water. The small air chillers were the next option and if mounted away from the room and temp differential is adequate it does a great job. Those are fairly cheap and easy to plump. Did not work for me because of where I live and the space I grow. So... when its hot, I put my grow toys up and fish. :-)

[RagWeedDWC]

I can not recommend one because of the cost and I want to fish :-). However I did test

https://www.amazon.com/dp/B07DH5BD5M/ref=sspa_dk_detail_0?psc=1&pd_rd_i=B07DH5BD5M

and looking to test https://www.amazon.com/dp/B07B7LBB47...d_i=B07B7LBB47 however with this one, I would need to design water flow for all my buckets.

[RagWeedDWC]

I failed to mention, do not use the hose included, get replacement black one. Took no time at all for alga to grow in the clear one.

[ocgreen]

Thanks all. They're a bit pricier north of the border but still much cheaper than the $500+ units I saw originally.

My main concern with this approach is that if i need one of these for every plant/bucket it seems like it would be a crazy amount of energy used... and wires/mess.

Now I'm starting to wonder if the most effective approach is to dramatically cool the room tents are in by using portable air conditioner. If I can get room cold enough then the air going to bubbles would be cooler and the cold air intake to tent would be cooler as well.

Or maybe I just need some type of inexpensive cover for my buckets while canopy develops. I read that bucket temp because easier to control once you have a full canopy.

Appreciate the tip about hose colour. If I do go this route, and I may buy one to try, I wouldn't have realized that until it was too late.

Thanks again

[DW2]

Howdy ocgreen, I keep my reservoir temperatures between 62°F and 70°F by using a 0.7 L ice bottle suspended into the reservoir (using an open bottom 3 3/4 inch net pot). Depending on the ambient temperature, the ice bottles usually last 4 to 6 hours between changes. Here's an old photo of the reservoir, the net pot (with the cover on it) keeps the bottle from floating away, requiring the top to be lifted for removal.

[ocgreen]

Hey DW2 you're helping me out all over the place today.

For my larger totes I'm finding the bottles are really effective. It's the 5 gallon buckets that heat up way too fast.

On one hand, I like how easy it is to do maintenance on the smaller buckets and you can move them around the tent easier to adjust canopy. Reservoir change for large reservoir was stressful!

On the other hand, the smaller reservoir temp spikes from 20C to above 25C overnight and I'm getting more ph fluctuations.

One thing I noticed about your approach is you're using larger bottles. So maybe that's something I can try. Maybe that extra bit to keep it frozen/cool overnight.

One thing I'm realizing... If i need to get a 70-100w chiller for every single bucket then it seems like we're getting into quite the electric bill. Can totally see why people shut down their space for the hot months (assuming you grow yourself enough to last).

[DW2]

ocgreen, it does not show up well in the photo, but I wrapped the reservoir with bubble wrap (the large bubbles) to provide some insulation. You could use the smaller bubble wrap or foam packing material, but I would not use fiberglass because if it gets wet (spillage or what ever) it night retain the moisture for a longer time, spills just run off the bubble wrap.

[RagWeedDWC]

Removing the exchanged air and plumbing something to drain the water it collects, I have looked but not tested using something like this. Mounting the unit outside the grow area and piping the cool air into the complete tent. https://www.walmart.com/ip/LG-8-000-...iABEgJHc_D_BwE
Jeezzzz Walmart, you could save money by shorting the links.....

[alltatup]

I sure hope you can concoct a home made solution to your problem. I could not: frozen water bottles didn't do much at all for me except melt really fast. so I ended up buying chillers for both my grow boxes, which keep the water at 67-68 degrees. First I had to deal with a bout of root rot from hell, and after that I got the chillers, which have been pumping away without a problem ever since.

This ain't no cheap hobby.

[Toker1]

Besides making a DYI shell and tube heat exchanger (aka a make shift water chiller), only other way I could think of is dig a deep hole in the ground, place the reservoir in the ground and pump the cool water up to your grow room. Geothermal cooling technique.

[ocgreen]

Appreciate everyone weighing in here.

The thought of root rot wiping out a crop makes me rethink my desire to cut corners. Luckily (for my plants) it just started snowing again just now -- can enjoy cold outdoor air for a while longer. 🥶

Did some rough math to help determine cost/benefit and wanted to share in case anyone else is considering the upgrade:

Costs

• 4x 100w chiller < $450 (CDN)
• 400w/mth 24/7 = $27/mth ($0.929/kwh avg)
• Maximum cost year one: $774
• Maximum yearly cost for energy only: $324

Benefits

• Water always stays within ideal range
• Less stress to plants
• Less maintenance (e.g. bottle swapping)
• Decreased chance for root rot
• Increased yields (as a result of above)
• Less worry and anxiety overall

I didn't put a dollar figure on benefits, but I'm left feeling like it's worth more than $27 per month. Hell I would pay more for just the last bullet point.

"This ain't no cheap hobby" is bang on.

[alltatup]

ocgreen RagWeedDWC I really appreciate your words!! I love to learn new things, and cultivating Cannabis has been a challenge--a real brain stimulant.

I'm happy with my learning curve. But I want to grow and cure the kind of bud where my weed buddies will hear the angels sing, their eyes will well up with tears from the sheer perfection of the high, it will take their breath away, they won't recognize themselves, and they will surf the tsumani-sized THC wave all the way to the shore.

Is that too much to ask for???

[RagWeedDWC]

Not to much to ask for, can I be on your friends list? :-)

[alltatup]

RagWeedDWC You betcha. You can be the first one to try the exceptional bud. ;-}