Other choices for algae control?

[Mags]

Hello. I’m new to the forum and a relatively inexperienced pond owner... although, I’ve learned a lot this past year so gaining better understanding quickly.
Over the winter I started getting that long stringy green algae and within 5 days it took over the pond. I started using an algae treatment recommended by my local garden pond store. It definitely worked as stated... within 3 days algae was 90% gone... but twice now it’s returned and had to re-treat. What I don’t like about this stuff is that when the water temp goes up it gets a bit more riskier to use without harming my fish. Apparently it depletes the oxygen levels in water and warmer pond water just amplifies that... so now onto my issue and actual question lol...
I have a small shallow pond in my courtyard - the deepest part is only 2-3 feet deep, so even with a shade guard and a little creek running into pond for circulation, pond water still gets
really warm in summer (Northern CA gets 3 digit heatwaves and usually in 90’s). The water gets very warm and is at the max level for what’s considered safe for my goldfish. Last summer they did fine but I had to top off pond with colder water every few days during heat waves. All that to get to this question- is there any other treatments or tips/tricks that work to keep the stringy algae at bay that are safer for my fish? Just FYI- I have a good filter and pump and pond has plants throughout, although they are only recently coming out of dormancy. Ph levels testing out fine. Also do I need to give up my little pond because it’s too shallow? That would be heartbreaking since I worked so hard on it -as you can see in pic- still working on it

 

[combatwombat]

Nice pond! How are you filtering your water? Algae = excess nutrients in the water. You need something to eat the nutrients before the algae can get to it.

 

[Jhn]

what is the size is the pond and how many fish? How much circulation?

Stop adding the algaecide as you have found out it is a bandaid and the dead algae just adds fuel to a pond that is already out of balance., which leads to more algae.

Adding a bog filter is the best solution. If you search bog filter on here you will find many build threads on how to do one. Adding aloooottt more fast growing plants to the pond even without a bog filter, which is simpler will prevent nuisance algae. Water cress, water celery, forgetmenots, creeping Jenny are all very fast growing plants that can be easily weeded out, as they grow removing nutrients from the pind and starving out the alga.

 

[brokensword]

definitely echo the CombatWombat and jhn; I've never added any chems to my pond and don't have either green pea soup water nor string algae--in the main pond. I do get it in a basin/river where I have a water hawthorn but it doesn't get out of control. The fish will actually eat at string algae, but it can get out of hand quickly.

Your pond would benefit from the fast growing floating plants like water hyacinth or water lettuce as you'll get shade for your 3 digit temp days and they'll reduce both light and nutrients for the algae. Many here do get the string algae in the spring but it goes away once our plants take off. As jhn notes. a bog really helps.

Also, goldfish are pretty tough, so you have some leeway with temps. Don't feed as much during really hot days, also, as they tend to slow down and should find the bottom of your pond where it's deepest and coolest.

 

[addy1]

Welcome to the forum!

Agree with all above

 

[j.w]

and welcome @Mags
Some here have used Hydrogen Peroxide. I never have tho and I don't know what the procedure for using it in a pond is exactly. Maybe do a google search.

 

[Lisak1]

Your pond is very pretty! I'll just say "see above" for algae control - chemicals "work" but because they only address the symptom and not the cause, the problem will keep coming back, as you have learned.

A shade cloth might help with the excess heat, in addition to the suggestion for more floating plants. You might even be able to use a patio umbrella - anything to add a bit of shade!

 

[addy1]

Some here have used Hydrogen Peroxide.

1 liter per 1000 gallons, then you need to pull out the dead stuff.

 

[poconojoe]

Yep, agree with all the responses.
Devise some type of shade. Put up poles and suspend some type of fabric that will block the sun.
Water lillies help create shade by their leaves covering the surface.
Floating plants are more two-fold. They not only provide shade, but they are very good at sucking up excess nutrients in the water, which will help starve out the algae.

UV lights, while some like them, I feel they are also sort of a band aid. They kill all the algae, including the good stuff. Plus, that dead algae turns into more food for more algae to feed on.

I'm also an advocate of bog filtration. They are a very effective way of filtering and there's no maintenance. No filters to clean out. They provide a place to grow plants.

 

[Mags]

Thank you! All great suggestions and helpful. After reading comments, I realized that when my pond plants were huge and lush, I had zero problems with algae. When winter came and my plants went dormant they died back pretty severely and that’s when the algae started, so now it all makes sense. We have pretty mild winters here so it’s just cold enough to cause plants to go dormant but just warm enough to keep the algae growing. Not sure what I’ll do about next winter yet, but I think I’m going to try the peroxide for a temporary fix now that my plants are quickly coming back and see how that goes. Also, going to start researching bog filters. Thanks again!

 

[addy1]

I filter only with a bog, is has been that way since 2010, turn the bog and pond on, crystal clear water no string algae no green water. Minimal care all summer, no filters to clean etc.

 

[Lisak1]

@Mags - remember when you're seeing algae growth that means you have excess nutrients in the pond. The algae may be the only thing keeping your water safe for your fish by consuming those nutrients. Look at the algae as more helper than nuisance. Maybe research if there are plants that will stay actively growing over your moderate winters.

And for sure I would consider not feeding the fish when the temperatures cool off - that just adds more waste to the pond which keeps that algae cycle going. How many fish do you have in your pond? How many gallons is it? An overstocked pond will be much more likely to respond with algae growth.

We've all been conditioned to "fight" algae growth, while nature is doing her best to keep things in balance. Some algae is very important to the bio-filtration cycle in the pond. And string algae is a big help in the early spring for all of us, before plants start to grow. Look at algae as both a symptom and a solution and you won't have that urge to "fight" it or eradicate it. Balance is the goal!

 

[jmajid]

Ditto to everyone's posts above, but i will add that when we were new to the pond, we used that same Algaefix and killed a LOT of koi/goldfish. We will never use that again... Be very careful how you use it.
Now, knowing a little more these days, aeration is critical if you do go ahead and use that or the hydrogen peroxide or any other treatment for algae... that and you need to be ready to pull out the dead algae.
A simple waterfall may not be enough aeration as the treatments work... use extra air pumps/bubblers.

Long term solution as you have mentioned yourself is to let your existing plants get up to speed after winter - they will out compete the algae. Add more floating plants if you can. Increase your biological filtration if you can - add a bog, even just a DIY container of some kind with pea gravel is a bog... doesnt have to be in ground and have streams etc.