Sodium percarbonate uses in fish ponds

[sweetpea]

Doc Roddy, do you have suggestions on the best way to treat
a "green water" pond? The air defuser is on but not the bottom
drain and filters. Should I mix in a bucket of water and then pour in
the pond?

Thanks!!

[FishOCD]

Doc Roddy, do you have suggestions on the best way to treat
a "green water" pond? The air defuser is on but not the bottom
drain and filters. Should I mix in a bucket of water and then pour in
the pond?

Thanks!!

Bump!

(I just went outside and in the last 3 days my pond has turned to pea soup but a little early to turn on pumps and UV.)

[sweetpea]

Bump!

(I just went outside and in the last 3 days my pond has turned to pea soup but a little early to turn on pumps and UV.)

Mine went green last fall within a week of turning the uv off.
It does every year but their colors are unreal in the spring.
That's when I finally get to see them.

Because of the weird weather this winter, I want to be able to check
them out soon.

[FishOCD]

I saw them last week and they are very bright (love that) but now... well TGFPO (thank goodness for platinum ogons) as they glow through the algae

[Sandyd]

Thanks Roddy.

What a find. I just ordered 15 bottles. I use liquid peroxide that you buy at Wally world in my laundry, cleaning around the house, etc.

This will be a plus to use to clean up things.

Sandyd

[Harveythekoi]

String algae and green water algae serve a purpose. They are mother natures way of regulating things in your closed system pond. If you just kill off either one, and this includes UV's there will be a reaction.

Whatever these algaes were feeding on is now free to further pollute the pond. If it was handling ammonia production by direct consumption then an ammonia spike could occur. With bio being dormant in the colder weather and many having their mechanical shut down something has to consume the waste from fish and decaying plant material. In most natural ponds there is at least water flow to carry things away and even these will get string algae and green water, again mother natures way of handling things.

I personally prefer to let the filtration clear things up, but I also understand being impatient. I can't even imagine colder weather places and having such a short time to enjoy the pond.

But I would recommend this, do not try this until your mechanical is in full swing. Once the string algae is killed if not removed it will decay and lead to other problems even if you get the bulk out right away. This will also allow the bio to catch up as quickly as possible.

The only plus I see is that besides killing the string algae the oxidation reaction from the peroxide created may help eat some of the decaying organics the algae was feeding on.

For green water I would be even more cautious in that there is much less for this to react with, oxidants are indiscrimnant, if they can't react with plant or other organics it will with the fish.

There are no magic elixers, there's a price to pay for everything. Roddy is a chemist and has a better understanding of these reactions than most. The average person should approach using any chemicals in the pond with extreme caution.

Action = Reaction. Know what's at stake before you kick mother nature in the shins. She has a mean streak and will right the pond with anything in her power including a fish kill to regulate load.

End of rant,

Garrett

[FishOCD]

String algae and green water algae serve a purpose. They are mother natures way of regulating things in your closed system pond. If you just kill off either one, and this includes UV's there will be a reaction.

Whatever these algaes were feeding on is now free to further pollute the pond. If it was handling ammonia production by direct consumption then an ammonia spike could occur. With bio being dormant in the colder weather and many having their mechanical shut down something has to consume the waste from fish and decaying plant material. In most natural ponds there is at least water flow to carry things away and even these will get string algae and green water, again mother natures way of handling things.

I personally prefer to let the filtration clear things up, but I also understand being impatient. I can't even imagine colder weather places and having such a short time to enjoy the pond.

But I would recommend this, do not try this until your mechanical is in full swing. Once the string algae is killed if not removed it will decay and lead to other problems even if you get the bulk out right away. This will also allow the bio to catch up as quickly as possible.

The only plus I see is that besides killing the string algae the oxidation reaction from the peroxide created may help eat some of the decaying organics the algae was feeding on.

For green water I would be even more cautious in that there is much less for this to react with, oxidants are indiscrimnant, if they can't react with plant or other organics it will with the fish.

There are no magic elixers, there's a price to pay for everything. Roddy is a chemist and has a better understanding of these reactions than most. The average person should approach using any chemicals in the pond with extreme caution.

Action = Reaction. Know what's at stake before you kick mother nature in the shins. She has a mean streak and will right the pond with anything in her power including a fish kill to regulate load.

End of rant,

Garrett

Well said. I am particularly shy about doing anything at all besides water changes until it is warm enough to start the pumps and filters.

[Roddy Conrad]

The filters were on, and had been on all Winter, and are oversized for the load, in both of the ponds where I have been using sodium percarbonate to clean the pond and kill the algae.

Certainly sodium percarbonate should NOT be used in a pond with no circulation or filter system.

I don't like the stringy algae. It is ugly, and makes a pond ugly, and the purpose of the pond is to be something lovely and relaxing in my yard. So out will come the sodium percarbonate if I have a serious string algae problem.

I used PP (potassium permanganate) the same way in the past, and still use PP to clean up the water since it is significantly less expensive for that purpose than sodium percarbonate. But sodium percarbonate is my choice for a pond with stringy algae or a lot of yuck that needs cleaning up.

Others can do it all kinds of ways that please them in their hobby, it is okay with me.

Diane, I have not had any green water to treat with the sodium percarbonate, but would expect it to easily kill green water algae.

[sweetpea]

Thank you, Doc Roddy

[Susan]

Will sodium percarbonate or PP eliminate the brown coloring from tanins in the water?

[Roddy Conrad]

Sodium percarbonate clears up the brown color in tanins in the water. So, YES, it does that.

PP will also clear tanins from the water in some circumstances, but sodium percarbonate will be more efficient at that particular problem.

[luke-gr]

Sodium percarbonate clears up the brown color in tanins in the water. So, YES, it does that.

PP will also clear tanins from the water in some circumstances, but sodium percarbonate will be more efficient at that particular problem.

Good to know. Roddy, care to elaborate on WHY the SP is better than PP in clearing up tannins?

[Roddy Conrad]

Good to know. Roddy, care to elaborate on WHY the SP is better than PP in clearing up tannins?

Because the sodium percarbonate is safe to dose at a higher oxidizer level than PP, and because sodium percarbonate is a bleaching agent from the hydrogen peroxide content that removes brown color from water.

I saw the tanins completely disappear in a few days in the treatment of our two water gardens last week, and the starting color of the water was dark brown from tanins. PP does not work that fast or that efficiently on tanin content of the water. To get rid of the tanins with PP takes much longer and is more dangerous to the fish in the water.

[Lee B]

The dose rate again?

2 lbs. per 1,000 gallons for the initial dose, and 2-3 Tbs. per week for maintenance?

[Roddy Conrad]

Please remember the LC50 information near the start of this thread:

The LC50 (dose at which 50% of the fish die if the dose remains active for two days and has nothing to react it away) of sodium percarbonate is 0.6 pounds per 1000 gallons. If there is something there like stringy algae or bottom yuck in the pond the hydrogen peroxide will be all gone in a few hours, so I indeed dosed my dirty water garden ponds with an initial dose of a pound per 1000 gallons, then used another pound per 1000 gallons the rest of the week to complete the cleanup.

Don't use a pound per 1000 gallons in a relatively clean pond, it would be too much.

If the brown color isn't gone, there is still stuff to consume the sodium percarbonate and its reaction product hydrogen peroxide.

Over on a stringy algae thread on KoiVet, someone asked me the good question of why not just use hydrogen peroxide itself? The answer is that if you buy the 3% hydrogen peroxide at Walmart in the hair care isle for this purpose, you are paying 5 time as much for the active hydrogen peroxide as you pay for the active hydrogen peroxide content in sodium peroxide, and you would need 4 gallons (16 of the one quart bottles at Walmart) of 3% hydrogen peroxide to be equivalent to the hydrogen peroxide content in a single 2 pound bottle of sodium percarbonate. And that is why it is so effective..........

[GloriaL]

Roddy, it seems I remember reading on some thread that adding H2O2 to stop the PP reaction would seriously lower your orp and could be bad for your fish. Does using the sodium percarbonate have that sort of effect on the orp?

[Roddy Conrad]

I dropped 168 grams (1.5 cups) of sodium percarbonate into our 4000 gallon indoor koi pond today to see the effect on ORP reading, since I have two on line calibrated ORP meters on that pond. The reading dropped immediately with the sodium percarbonate addition from 300 to 140, then the reading started slowly climbing back up, and is up to 210 in about a hour.

The drop of ORP with hydrogen peroxide reversal of PP is similarly abrupt, then the next day the ORP is back up to the normal value. The issue with using peroxide to reverse active PP is the sudden shock of such large changes in the oxidation state. Adding sodium percarbonate to water that has no active PP will not be as abrupt a change.

The effect of hydrogen peroxide (and/or sodium percarbonate) on ORP is a strange effect. I need to read up on oxidation potential technology some more to understand it.

[GloriaL]

Thanks for the experiment and the info. How long did it take to go back up?

[Roddy Conrad]

I got the following questions privately and decided to answer them publically:

1. PP does it actually oxidize nitrates?

Roddy: Actually, I don't know whether PP does or does not oxidize nitrates. This is not the first time someone has asked that question. I need to set up a controlled experiment to answer that specific question. My answer today is simply that I don't know whether PP does or does not oxidize nitrates.

2. Okay my system is up and running pond size is 1920 gallons. I use 1.2 pounds of SP. Does that get the crud on the bottom of the pond too?

Roddy: The sodium percarbonate will get the crud on the bottom of the pond if you use enough of it to do the job. How much will depend on the thickness of the layer of crud and how much other stuff you need oxidized by the hydrogen peroxide.

3. Does the SP do oxidize as well as the low level pp? Do I need to do both, or just use the SP when there is String Algae?

Roddy: I have not used the sodium percarbonate long enough to know whether it oxidizes pheromones, the antigrowth regulator. I don't know yet whether sodium percarbonate is or is not a good replacement for regular low level PP treatment and all the things it does for pond maintenance. Certainly the sodium percarbonate does many of the same things as low level PP treatment, and certainly it is safer for the fish, and it is pretty cheap to buy (like PP which is also cheap when bought in the right places).

4. Will the SP work on an algae bloom, or pea green soup. I have a friend who can't keep his pond clear.

Roddy: Sodium percarbonate should kill pea green soup algae as well as string algae. I never get pea green soup algae, so can't give you a first hand account of that use. Even my crudest filter system always keeps pea green soup algae under control with my other practices.

Gloria, the ORP of the indoor koi pond data today:

ORP reading before adding anything: 300 - this is a well maintained pond indoors with a huge filtration system that stays at high water quality every day of the year.

ORP reading right after dumping in 1.5 cups sodium percarbonate: 130 to 140

ORP reading an hour later: 210

ORP reading 3 hours later: 260 - I expect the reading to be at 300 again tomorrow morning as usual after hydrogen peroxide "does its thing".

[GloriaL]

Thanks Roddy