Does hydrogen peroxide kill nitrifying bacteria when dosed correctly?

[hamstermann]

I can't really afford more plants right now. My marsh marigold has kicked the bucket and my other plants are either still sleeping (this is the first year for them) or not growing fast enough to outcompete the string algae. if i dose the pond with 1/2 cup H2O2 per 100 gallons (which is the recommended ratio in a couple of articles I've read this morning) am I going to kill off my good bacteria?

my thought is that by killing off the string algae and removing it, i'll remove the nutrients that made it grow. If more forms, I'll repeat the process until either winter comes or the pond finds its balance but i can see where that might be shooting myself in the foot if it kills the bacteria I need for pond health.

 

[WaterGardener]

No. However, you won't remove the nutrients by removing the algae. The algae is there because of the nutrients. They came first.

 

[hamstermann]

No. However, you won't remove the nutrients by removing the algae. The algae is there because of the nutrients. They came first.

thanks. the algae was formed using the nutrients so once it's dead and i get it out, it doesn't break down and become nutrients again which would compound the problem. does that make sense?

i know algae forms from having excess nutrients but killing it and removing it also removes that much more potential nutrients from starting the cycle again.

 

[WaterGardener]

That is true, but if you don't address the original situation of too many nutrients, the algae will come right back.

You may need more filtration, less feeding, fewer fish, things of that nature to deal with those nutrients.

Shading the pond would also help.

Maybe the pond just needs more time to mature and balance itself. That can sometimes take years.

 

[Lisak1]

You definitely want to remove as much of the algae by hand as you can. You are correct - dead algae just feeds more algae. HOWEVER remember that the algae is doing the job that your plants are not - without the algae your pond may become unhealthy for your fish. So while you want to control the excess, be grateful for the balance it's creating in your pond in the meantime!

And no - H202 won't kill bacteria at that level.

 

[combatwombat]

Agree w/ @Lisak1. Remove as much manually as possible before dosing, I would turn off the pump and dose the h2o2. If you have a lot of algae, the h202 it'll burn itself up quickly on all the organics in the pond long before it can make it to your bio fliter.

Probably going to work a lot better for you by applying topically. Works best above water and just below. Harder to get the deep stuff.

You can also get a case of test strips to test for h2o2 levels and check for absence before turning the pump back on if you're really worried about it. But I wouldn't be.

 

[Jhn]

@hamstermann Yes, by removing algae be it dead or alive, will remove the nutrients from the pond that is stored in the mass of the removed algae.
Really any form of plants in our pond are actually nutrient banking vehicles, once you remove the plants be it algae or higher plant forms, then You are doing nutrient removal.

 

[hamstermann]

Thanks everyone. I did dose with H202 and it may have killed a little of it, but I'm not seeing a real difference. I kind of waver between wanting to dose again after manually removing what I can or just giving up on dosing and stick with manual removal. Anyone know or have an educated guess on how many times I can dose before it becomes dangerous? Sounds like @combatwombat was saying it's actually really hard to do it too many times because it breaks down easily.

 

[WaterGardener]

It breaks down pretty quickly, so I doubt you can do it too many times with the 3% solution.

 

[combatwombat]

I don't think there's any risk of doing it too many times. Risk is in doing too much at once (fish kill). That would also be difficult to do with 3% concentrate in a pond of any significant size.

 

[hamstermann]

Thank you both!