Bromine tablets in sea strainers?

[oak_box]

I'm on an inland lake.

A couple of friends have suggested putting hot tub type bromine tablets (about 1-2" disks, similar to chlorine, slow dissolving) in the sea strainer to discourage the dang Zebra Muscles from growing there. Might also reduce algae growth - though I'm guessing there's not enough light in the engine room for algae to grow.

While chlorinating the zebra muscles *might* work - I'm a bit concerned that the water flow through the strainers will dissolve the tablets very quickly. I'm also a little concerned about whether it would have any negative impact on the engine internals...

And finally - if it was such a great idea, I'm assuming people would also do it for barnacles in salt water.

Has anyone heard of, or done this?
Does it work?
Is it a bad idea?

 

[OldDan1943]

What will protect the through hull strainer?
I put bromide tablets in the condensate trays of the A/Cs

 

[HeadedToTexas]

Does not sound smart to me. Bromine will attack all sorts of metals and corrosion is irreversible.

 

[rclarke246]

I put these bromide tablets in my A/C strainers every 3-4 weeks for 9 years. Good luck, so far.

 

[Alaskan Sea-Duction]

Would love to hear about the result.

 

[HeadedToTexas]

Me too. Bromine and bromide are as different as chlorine and chloride. Most "bromine" tablets are bromohydantoin and dissociate to bromine. What are you using?

 

[Seevee]

I've heard that a small copper strip will work.

 

[OldDan1943]

The condensate pans on my A/Cs are some sort of plastic so the bromide tablets do not attack the pan. I did have trouble with algae build up in the condensate overboard lines, not any more.

 

[TWedd]

I have heard this, and even used bromine tabs in my strainer. Couldn't tell if it helped. I recently helped a neighbor replace his A/C units, and the manufactures literature warned against using bromine for cleaning the condensers. I don't use the bromine tabs any more.

 

[AnsleyS]

One can also try putting a copper pipe piece or copper elbow etc in the strainer. Copper is less corrosive than halogens.

 

[rgano]

One can also try putting a copper pipe piece or copper elbow etc in the strainer. Copper is less corrosive than halogens.

Been doing that for decades in saltwater. Can't imagine zebras would care for it either.

 

[OldDan1943]

Been doing that for decades in saltwater. Can't imagine zebras would care for it either.

At most it will protect from the sea strainer through the A/Cs. What is going to protect the though hull to the strainer?

 

[rgano]

At most it will protect from the sea strainer through the A/Cs. What is going to protect the though hull to the strainer?

Dunno that it does not since they are very close together.

 

[OldDan1943]

Dunno that it does not since they are very close together.

I would think the through hull opening would plug up first.

 

[Engineman3rd]

I've heard that a small copper strip will work.

I have been told by some one that I trust that putting copper in the strainers is a myth.

 

[rgano]

I would think the through hull opening would plug up first.

Never saw it happen.

 

[rgano]

I have been told by some one that I trust that putting copper in the strainers is a myth.

I have no specific data to say either way, only my own ever-clean ac strainers.

 

[psneeld]

I have been told by some one that I trust that putting copper in the strainers is a myth.

With so many things in boating, people's experience with different materials and methods can vary wildly.

Some things can be bad, like substances that deteriorate boat parts and others that won't hurt but may do little or nothing at worst, or do what you want at best.

So once you gather internet and other possibly expert advice, sort through it, apply what good/bad can happen and experiment if there is no industry standard for things like this.

 

[JDCAVE]

Why don’t you do an experiment to test the theory with by doing this in fresh and salt water with stainless, bronze and copper parts in a plastic container? Seems like a way to go before you risk the strainer. That stainless part is not cheap to replace.

Jim

 

[OldDan1943]

If you try the copper, remember to sand it good to get the remove all the oxidation off and put it in the strainer quickly before it begins to oxidation.

 

[Comodave]

If you try the copper, remember to sand it good to get the remove all the oxidation off and put it in the strainer quickly before it begins to oxidation.

Do you insulate it from the S/S basket?

 

[OldDan1943]

Do you insulate it from the S/S basket?

I don’t use copper.
I had an on low flow no problem, repeatedly. I had the over board hoses replaced. No more problems for over a year.

 

[Wildbill]

I'm confused about putting copper into the strainer, I'm no chemist for sure..copper is a pretty inert metal, and what is the hope, that it gives off copper sulfate, which is toxic to marine life, pretty doubtful on seawater or fresh as you'd have to actively trade ions I'm thinking...could be wrong...have been Many times before

 

[HeadedToTexas]

Presumably the hope is that the copper slowly dissolves to yield copper ions into the water, which is the same thing copper sulfate does. It's the copper that is toxic to invertebrates, not the copper sulfate.

Copper develops a beneficial oxide layer that slows corrosion to the point that I can't see a copper strip donating enough copper ions to the water to impact much. Might be a different story if you create a galvanic cell where the copper is the anode. Stainless would do that.

Still, my bet would be on the zebra mussels or whatever grows in your neck of the seas.

 

[rgano]

There was a reason that the sailing ships of yesteryear were covered with copper sheathing.

 

[phillippeterson]

There was a reason that the sailing ships of yesteryear were covered with copper sheathing.

Why aren't boats still covered with copper sheathing?

 

[rgano]

Why aren't boats still covered with copper sheathing?

Have you looked at the copper content of the best anti-fouling paints?

 

[riverfrontauthor]

I put a handful of 1” chlorine tabs in my strainer every two weeks in summer (every 4 to 8 weeks in winter) and far better than keeping the strainer clean - ish they do a great job of cleaning the lines past the pump.

I’ve been doing this for about four years and have yet to need to reverse flush the air con units.

I use two marinaire 16k units.

I got another guy at the marina to also do this.

He used to twice a year have to reverse flush and hasn’t for two years.

I do NOT know how the chemistry of chlorine on copper tubing will work long term but I was really hoping to get ten years out of these units and I’m about halfway there with a boat chilled enough that the dog sleeps under the blankets most days

 

[rgano]

Lucky dog!

 

[Woodland Hills]

I put a handful of 1” chlorine tabs in my strainer every two weeks in summer (every 4 to 8 weeks in winter) and far better than keeping the strainer clean - ish they do a great job of cleaning the lines past the pump.

I’ve been doing this for about four years and have yet to need to reverse flush the air con units.

I use two marinaire 16k units.

I got another guy at the marina to also do this.

He used to twice a year have to reverse flush and hasn’t for two years.

I do NOT know how the chemistry of chlorine on copper tubing will work long term but I was really hoping to get ten years out of these units and I’m about halfway there with a boat chilled enough that the dog sleeps under the blankets most days

As long as there is no plastic in the system chlorine is ok. But bromine will not harm plastic if there is any there. Better safe than sorry later.....