Green Water

[Lisaebetten]

What do you have for filtration? Under-filtered ponds have a good chance of going green. Also please tell us how many fish you have and how large they are. Overstocking can also contribute to green water.

One procedure that is simple and will have no bad side effects whatsoever is to aerate your biofilter. Green water algae and the nitrifying microbes compete for ammonia. By giving the biobugs some extra oxygen you give them a competitive advantage.

would that be putting an aerator directly into your bio filter? Or will it be o.k. in the lower section of the pond?

 

[shakaho]

Just put an airstone in the filter just under the biomedia.

 

[Dave 54]

Just put an airstone in the filter just under the biomedia.

In layman's term's, Algae though single celled act as one when producing oxygen for your pond whiich is why they are partly a good thing and like you say an energy food for your fish but it also has a darker side in that it also produces CO2 at night robbing the pond of ozygen because the process reverses.
Which is why many employ bubblers on our bottom drains are airstones to our ponds the other reason we dont like it in our ponds is because you cannot see your fish


Dave

 

[Lisaebetten]

In layman's term's, Algae though single celled act as one when producing oxygen for your pond whiich is why they are partly a good thing and like you say an energy food for your fish but it also has a darker side in that it also produces CO2 at night robbing the pond of ozygen because the process reverses.
Which is why many employ bubblers on our bottom drains are airstones to our ponds the other reason we dont like it in our ponds is because you cannot see your fish


Dave

Thanks, I wanted to add a bubbler to my pond to keep from getting any dead spots but didn't want to see a bunch of bubbles that doesn't look like a natural pond. Would an aerator be o.k. to put in the bottom to keep good circulation? I'm hooking everything thing up within the next week.

 

[crsublette]

Thanks, I wanted to add a bubbler to my pond to keep from getting any dead spots but didn't want to see a bunch of bubbles that doesn't look like a natural pond. Would an aerator be o.k. to put in the bottom to keep good circulation? I'm hooking everything thing up within the next week.

Yeah, an aerator would be ok when put on the bottom to keep good circulate. If you don't want to see a bunch of bubbles, then I know of many folk that have installed an electronic timer to control when the aerators goes on/off so the aerator automatically turns on during the night and turns off during the day.

 

[John & Eleanor O'Connor]

Welcome to our Group! Where do you live? Some use aeration that works, some use uv, sometimes it is how much you feed, i.e. too much, I control mine with my filter which is a large peagravel and plant bog

We live in Hertfordshire, UK. The peagrave and plant bog sounds a good idea. We'll try it.

 

[John & Eleanor O'Connor]

We never have your problem and like your pond its in full sun, however there can be many causes for gree water exessive nutrients in the water being just one of them filters that arent man enough to do their job another .
When was the last time you cleaned both the bottom of the pond and your filters please?
How much do you feed your fish each day ?
You could try adding Montmarrilioniteclay which acts as a Flucculant attracting the algae to it then deposting it in your filters Quilt batting often helps too
Hope this helps you cure things


Dave

Hello Dave

We clean the bottom of the pond every autumn and the filters probably every couple of months. We feed the fish 2/3 times a day during spring summer and autumn and only when the temperature outside is above 10 degrees centigrade. Thank you very much for all your suggestions.

Eleanor

 

[John & Eleanor O'Connor]

I sometimes wonder if it's the treatment "with various products" that extends and prolongs the green water battle. We've never had green water but I'm sure it's frustrating that the desire to clear it up is strong - we only have so many months to enjoy our ponds and fish, after all!

I would try the more natural (or at least non-chemical) approaches - aeration, mechanical filtration (quilt batting, as Dave suggested), cleaning existing filters and doing frequent water changes, etc. How many fish do you have and how often do you feed them? We can sometimes unintentionally add to our own problems with overfeeding or overstocking. And I suppose if you can't see your fish, you may not even know!

Good luck - I'm sure it's frustrating when you just want to see your fish and enjoy your pond!

Hi Lisa,

We have about 30 fish and feed them 2/3 times a day between spring and autumn.

 

[John & Eleanor O'Connor]

Yeah, if the pond products are not helping, then I would definitely stop using them.


If this is the floating variety of algae, then simply having a UV bulb does not resolve this. These UV bulbs must have a proper water flow, which is stated with the UV device. A too fast water flow will negate the results from the UV bulbs. For example, the UV device says it is recommended with a 900gph flow and your pump is 1200gph. If you directly connected the pump to the UV device, then the water would be moving too fast thus preventing the UV bulb from properly functioning; so, to fix this, then a bypass line is created. The UV is connected to the bypass while the main line goes directly to the pond or wherever you desire. Everyone sets these up differently, but, personally, since I want to make sure I know where the water is flowing, I place a valve on the bypass line and the main line. So, if your pump is 1200gph and the UV device recommends a 900gph flow rate, then, since the UV is on the bypass line, open the bypass line by one-third open and close the mainline by one-third closed since 1200gph is approximately 33% higher flow rate than 900gph.

Look into using some quilt batting and possibly building a small bog. These filter to filter out the algae by either directly removing some of the floating algae (with the quilt batting) or by trapping the floating algae inside the gravel so to be consumed by other microorganisms (with the bog).

Look into do slow major water changes, of around 40% or higher, every day or every couple to few days.

Also, the fish might be getting fed too much.

There is the possibility of there being too many fish in the 2100 gal pond resulting in some of the fish needing to be re-homed, but I first try the other recommendations stated above and by others rather than jumping the gun to re-homing the fish; this is only the last resort.


Keep in mind... The significant amount of dense floating algae is present due to a significant amount nutrient production and excessive nutrient residual . So, when this algae is reduced, then you may likely notice an increase in ammonia or nitrates. So, keep an eye on the ammonia or nitrates while you are dealing with removing the floating algae.

 

[John & Eleanor O'Connor]

Wow!! that's a lot of information. I can see We've got a lot to learn - better get on with it!

Eleanor