Potassium hydroxide for pest control

[JVU]

I was listening to the most recent Reef Beef. Rich @Thales was talking about treating Aiptasia and other pests with liquid potassium hydroxide (aka caustic potash). I don’t think it was mentioned what concentration he uses, or what is the max amount he uses per treatment. He did mention that he injects it into the pests with a needle, but Ben also mentioned it makes a paste, so maybe laying it on top works? Wondering if anyone knows more about this, especially what concentration, and any personal experiences.

Also, wondering why not to use sodium hydroxide (aka lye)? This has been used for years for similar applications, squirting on top of the pests. I’ve seen concentration of 2N used, which is quite potent.

AND wondering people’s thoughts on if either of the above is the magic ingredient in F-Aiptasia since it also forms a paste that hardens, is caustic, and can raise pH and alkalinity like KOH and NaOH do.

 

[Thales]

Thanks for listening!

This is the stuff I have been using for concentration info.

Amazon.com

www.amazon.com

I started looking this direction because I wanted for see if I could find something that was off the shelf that wouldnt hurt me if it touched me - I didn't want to mess with mixing and diluting. Laying it on top can work, but injecting is more effective IME. It doesn't really make a paste, it kinda keeps to itself if that makes any sense

 

[JVU]

Thanks for listening!

This is the stuff I have been using for concentration info.

Amazon.com

www.amazon.com

I started looking this direction because I wanted for see if I could find something that was off the shelf that wouldnt hurt me if it touched me - I didn't want to mess with mixing and diluting. Laying it on top can work, but injecting is more effective IME. It doesn't really make a paste, it kinda keeps to itself if that makes any sense

Thanks Rich. So that solution is 10% concentration, which is about 2 N (actually 1.8 N I think).

You should try using 2 N NaOH if you haven’t already. It’s pretty similar, has a long track record of use to kill pests in reef tanks, and is about an order of magnitude cheaper. Similar safety considerations. It’s lye, also used in drain cleaners. Lots of people have started using it as their alkalinity dosing because it raises pH. I don’t hear it talked about much though for pest removal. No additional concerns regarding by-products. I haven’t used either myself but I’m considering to soon. I’d be interested to hear what you think of it.

Here’s an interesting article from 2002 about it:

aiptasia control

www.reefscapes.net

 

[Thales]

Thanks Rich. So that solution is 10% concentration, which is about 2 N (actually 1.8 N I think).

You should try using 2 N NaOH if you haven’t already. It’s pretty similar, has a long track record of use to kill pests in reef tanks, and is about an order of magnitude cheaper. Similar safety considerations. It’s lye, also used in drain cleaners. Lots of people have started using it as their alkalinity dosing because it raises pH. I don’t hear it talked about much though for pest removal. No additional concerns regarding by-products. I haven’t used either myself but I’m considering to soon. I’d be interested to hear what you think of it.

Here’s an interesting article from 2002 about it:

aiptasia control

www.reefscapes.net

I take the NaOH precautions seriously, so seriously that I have stayed away from it. How harsh is 2n on people? The 10% stuff I am using makes you slippery, but washes off with no problem. Thanks!

 

[Thales]

This one says 2m, same thing?

Amazon.com

www.amazon.com

Thanks

 

[Darkxerox]

I take the NaOH precautions seriously, so seriously that I have stayed away from it. How harsh is 2n on people? The 10% stuff I am using makes you slippery, but washes off with no problem. Thanks!

For 2N you'd still get in trouble with no PPE in the lab with county inspectors! I'd definitely wear eye protection, nitrile gloves, and not wear any clothes you care about while using it. Secondary containment too is good.

 

[Thales]

For 2N you'd still get in trouble with no PPE in the lab with county inspectors! I'd definitely wear eye protection, nitrile gloves, and not wear any clothes you care about while using it. Secondary containment too is good.

Yeah, but you would get in trouble for 10% HCL as well and that stuff really doesn't do much to your skin. What is the reality of 2N if you get it on your skin?
However if it could really do damage to your skin, I am not a fan for the hobby in general.

 

[Darkxerox]

Yeah, but you would get in trouble for 10% HCL as well and that stuff really doesn't do much to your skin. What is the reality of 2N if you get it on your skin?
However if it could really do damage to your skin, I am not a fan for the hobby in general.

I think it's more risk to your eyes and mucus membranes, here's the MSDS

Then again a lot of daily household products and tank inhabitants would fit into that criteria.

 

[Thales]

This one says 2m, same thing?

Amazon.com

www.amazon.com

Thanks

2n and 2m are the same, so ordered. If this doesn't burn my skin instantly, I'll let you know. That it is available mixed and ready for our application makes it more useful IMO.

 

[JVU]

@Thales
M=N for both KOH and NaOH (because they have 1 OH group).

The KOH you are using is about the same strength FWIW Rich. The slipperiness you feel is the fat being rendered out of your skin (saponification) as the outer layer is melted off by the caustic nature of the OH.

Gloves highly recommended, eye protection required.