Algae control

[bfindey]

I'm not sure if this is the appropriate thread to post this question....however, technically algae is a plant so here goes. I have a 1200 gallon pond that gets full sun most of the day, I have 6 very young koi about an inch and a half long. The pond is just over a year old. About once every two weeks I do a 20% water change, put in beneficial bacteria (I can't remember the name of the product but its from Microblift is purple and smells terrible) and a detoxifier that removes ammonia, nitrites, and nitrates. I used to use an algacide to keep the algae down. I had read that trapdoor snails are good to help control algae and I thought they would add some interest in my pond. Since then, I've seen varying reviews on that. Never the less, I now have 50 trapdoor snails in my pond.

Ok now that you have all the particulars, time for the question. I'm getting a lot of this really powdery looking green algae looking stuff laying on the bottom of my pond and what I'm assuming is string or hair algae growing on the sides and on some of the rocks. While I can see the snails going to town on this stuff, they aren't getting it all. I don't want to kill or remove the snails. Is there any algaecide that I can use that will not kill my snails?

Thanks in advance!

 

[Koi4JT]

I'm not sure if this is the appropriate thread to post this question....however, technically algae is a plant so here goes. I have a 1200 gallon pond that gets full sun most of the day, I have 6 very young koi about an inch and a half long. The pond is just over a year old. About once every two weeks I do a 20% water change, put in beneficial bacteria (I can't remember the name of the product but its from Microblift is purple and smells terrible) and a detoxifier that removes ammonia, nitrites, and nitrates. I used to use an algacide to keep the algae down. I had read that trapdoor snails are good to help control algae and I thought they would add some interest in my pond. Since then, I've seen varying reviews on that. Never the less, I now have 50 trapdoor snails in my pond.

Ok now that you have all the particulars, time for the question. I'm getting a lot of this really powdery looking green algae looking stuff laying on the bottom of my pond and what I'm assuming is string or hair algae growing on the sides and on some of the rocks. While I can see the snails going to town on this stuff, they aren't getting it all. I don't want to kill or remove the snails. Is there any algaecide that I can use that will not kill my snails?

Thanks in advance!

I used to have issues with algae a long time ago. I also had a nice multi-stage filter that I had to clean every week (1500 gal pond with a lot of Koi and goldfish). And yes, I did use chemicals and pond plants to try and maintain the water quality. Then, I did some research and built a bog which is about 6' long by 2' wide by 4' deep, filled with pea gravel and has ornamental grass growing on top. Ever since I built the bog, my pond's water quality has been clear and excellent. About every three years, I back wash the bog. Since then, I have not used chemicals or anything else to maintain the pond water quality. I just feed them and enjoy them. By the way, for reasons unknown, the algae and crud grow and exist only in and on top of the bog, which is easy to clean and maintain.

 

[Meyer Jordan]

You do not mention biofiltration. Do you have a biofilter on this pond.?

 

[Koi4JT]

The bog is the bio-filter. I periodically clean out algae on top of the bog when it gets really thick. Then once a year, about now, I will block the water chute to the pond then remove some of the surrounding masonry support blocks to let the bog overflow onto the ground. I then run the pond pump which allows the bog to overflow onto the yard to flush away most of the muck that accumulates on top of the pea gravel. If you choose to build a bog, it should be higher than the pond so it can freely drain back into the pond. Also, you need to install a check valve on the supply line to the bog to prevent the bog from siphoning all of the accumulated crap back into the pond. Hope this helps.

 

[Koi4JT]

The bog is the bio-filter. I periodically clean out algae on top of the bog when it gets really thick. Then once a year, about now, I will block the water chute to the pond then remove some of the surrounding masonry support blocks to let the bog overflow onto the ground. I then run the pond pump which allows the bog to overflow onto the yard to flush away most of the muck that accumulates on top of the pea gravel. If you choose to build a bog, it should be higher than the pond so it can freely drain back into the pond. Also, you need to install a check valve on the supply line to the bog to prevent the bog from siphoning all of the accumulated crap back into the pond. Hope this helps.

Oh, when you essentially backwash the bog as i previously mentioned, you will need to add water back into you pond to replace the water used to clean the pond.

 

[Meyer Jordan]

If you have a 'bog' and are having algae issues, the obvious answer is that you either have too many fish or you are overfeeding.
I would recommend putting these pond treatments that you have been using on a shelf someplace and forgetting where you put them. They are not doing anything to moderate your problem.
A question on your 'bog'....Is it an upflow or downflow system?

 

[Meyer Jordan]

I'm not sure if this is the appropriate thread to post this question....however, technically algae is a plant so here goes. I have a 1200 gallon pond that gets full sun most of the day, I have 6 very young koi about an inch and a half long. The pond is just over a year old. About once every two weeks I do a 20% water change, put in beneficial bacteria (I can't remember the name of the product but its from Microblift is purple and smells terrible) and a detoxifier that removes ammonia, nitrites, and nitrates. I used to use an algacide to keep the algae down. I had read that trapdoor snails are good to help control algae and I thought they would add some interest in my pond. Since then, I've seen varying reviews on that. Never the less, I now have 50 trapdoor snails in my pond.

Ok now that you have all the particulars, time for the question. I'm getting a lot of this really powdery looking green algae looking stuff laying on the bottom of my pond and what I'm assuming is string or hair algae growing on the sides and on some of the rocks. While I can see the snails going to town on this stuff, they aren't getting it all. I don't want to kill or remove the snails. Is there any algaecide that I can use that will not kill my snails?

Thanks in advance!

What have you provided for biofiltration?

 

[Lisak1]

Too. Much. Treatment.

Algaecide only exacerbates the problem by killing off algae and adding to the nutrient load in the pond. Dead algae=more algae. If you want to clear up the algae, stop with the algaecide. Oh and yes - it can kill your snails. As well as all the other microscopic life in your pond.

Bacteria in a bottle, while it's not going to hurt anything, isn't really doing anything for your pond either. And it's probably costing you money. So scrap it.

You're adding a detoxifier - why? Do you have evidence from testing that you have high ammonia, nitrates or nitrites? If not I would ask why you are treating for a problem that you aren't sure you have.

I won't re-open the water change conversation here - for more on that topic read this thread:

https://www.gardenpondforum.com/threads/question-on-water-change.22170/

It's long, but it's a great in-depth discussion on the various opinions on water changes in a garden pond. Well worth your time to read.

As for your powdery algae - could be that's the dead stuff that is accumulating from your algaecide treatments.

Go back and read your first sentence - technically algae is a plant. You need to remember that algae is not in and of itself a problem. It's a symptom of a problem - basically the nutrient load in your pond is too high. So either you have too many fish (which doesn't appear to be the case), you overfeed your fish, you don't have enough filtration (mechanical and/or biological) or nutrients are entering your pond from another source i.e., fertilizer washing in from the surrounding area. But excessive algae growth is both telling you that you have a problem and also helping your pond deal with the problem.

And for the record - a healthy pond WILL have algae. You want algae in your pond. You just don't want it overtaking your pond.

So back to @Meyer Jordan 's question about filtration - what do you have going on in your pond for filtering?

 

[Koi4JT]

If you have a 'bog' and are having algae issues, the obvious answer is that you either have too many fish or you are overfeeding.
I would recommend putting these pond treatments that you have been using on a shelf someplace and forgetting where you put them. They are not doing anything to moderate your problem.
A question on your 'bog'....Is it an upflow or downflow system?

I think that you may have misunderstood me. Prior to building the bog, my pond would develop algae. After building the bog, my pond stays crystal clear all year long. However, the top of the bog will develop a carpet of algae in hot weather which can easily be removed by hand. I have not needed any chemical support for the pond, except when I add water, since employing the bog. As for the bog, it is an up-flow design with a discharge chute into the pond. The supply piping has a check valve to prevent back flow when the pump is turned off for maintenance. I hope this clarifies things.