Sciencemadness Discussion Board

How to prevent mold in a home made evaporative cooler?

AdamAlden - 1-10-2020 at 11:41

Im looking for something to prevent mold and insects from growing... So far with plain water it grows insects mainly... I added neem oil and that killed the insects but made it grow mold. I want to try sodium hypochlorite (only thing in the house atm) but im also thinking about holding off and using some chlorine tablets from my parents pool supply. I just dont wanna add something that's going to fill my room with fumes. Thank you!!

I also tried hydrogen peroxide but that only lasted a couple of days and seemed to cause mold growth. I had this running for 4 months without cleaning it. Just cleaned it today.

I have some ph up and down could I change the ph to prevent mold? this stuff is for hydroponics. should be safe and no fumes.

[Edited on 1-10-2020 by AdamAlden]

macckone - 1-10-2020 at 12:22

BAC is probably better but yeah sodium hypochlorite should be fine as long as you have a mist collector before the blower.
In Commercial systems they usually use BAC which is available as a mold preventative online.

Note that you need to dissolve and dilute and you have to have a mist collector.

AdamAlden - 1-10-2020 at 13:11

I looked up BAC and it seems perfect but there doesn't seem easy to get it (it's quite expensive) so I will order those tablets as that will be enough to last for years. Thanks for the info I really appreciate it!

I'm not going to try the bleach as I have no mist collector. Mist collector might be a fun project in the future!

TriiodideFrog - 2-10-2020 at 00:56

Maybe try some vinegar, but I don't fancy acetic acid fumes. The vinegar worked on normal mold but I am not sure about the one in the evaporative cooler.

Tsjerk - 2-10-2020 at 03:49

Use oxone, it is even used to sterilize glass before bottling perishable drinks.

B(a)P - 2-10-2020 at 03:52

From personal experience clove oil works well for mould. Not sure how it performs for insects.

unionised - 2-10-2020 at 04:14

It isn't mould you should be worrying about.

Quaternary ammonium compounds are pretty good biocides and you can get them fairly cheaply.

macckone - 2-10-2020 at 06:23

I provided the link to a version, 20% BAC.
You can look for evaporative cooler sanitizer or swamp cooler sanitizer on a local search engine since amazon is probably not the best for you.

Herr Haber - 2-10-2020 at 07:41

BAC ? Benzalkonium Chloride ?

I just received 1 liter of 50% solution this week for less than 15 Euros. Never saw it in tablet form though.
Got it from a drugstore who has plenty of hobby, household, gardening chemicals and supplies of all sorts. These are getting very scarce around here :-/

AdamAlden - 2-10-2020 at 11:03

good god! legionella?! I'm just going to get a packet of pool shocker and add a little to sterilize it. I'll let the chlorine sterilize the system (I just rinsed it off because I'm lazy) and see how it goes. I'll order those tablets macckone if the pool shock is unbearable. I'm hoping my room just smells like a pool. It had white stuff growing on it and it smelt like a wet dog when i turned it back on.

AdamAlden - 2-10-2020 at 12:38

I added some "sodium dichloro-s-triazinetrione dihydrate". it says 2.5 tsp per 500 gallons but i didnt read that before i added about a whooping tea spoon to like 10 gallons. I am definitely getting that spa feeling that I get when im in the spa area in the gym. No noticeable odor.

Dr.Bob - 9-10-2020 at 17:15

Just use tritium oxide in it, that should keep anything from growing in it...

Sodium carbonate might be basic enough to prevent some things, but benzyl,alkylammonium chlorides are good for that.

macckone - 29-10-2020 at 08:19

Herr Haber, yes BAC is available in tablet form, at least in the US.

Dr. Bob, tritium oxide is how you wind up with a 500 ton protoplasm terrorizing the town aka the blob.
Tritium oxide is insufficiently radioactive to kill bacteria but the mass difference does interfere with normal biological process. In plants it just makes them sickly and a 'failure to thrive'.

Pyro_cat - 19-11-2020 at 18:17

UV light ?

macckone - 22-11-2020 at 21:37

Pyro cat,
That would work.
The turbidity of the water would have to be managed and it has to be at killing luminance.
Particularly algae can thrive if it doesn't kill it.