How To Stop Pond Water Going Green So Quickly?

[Richb2004v2]

How do I stop my pond water from going green? It is a small pond with a little shade from surrounding plants, but after a week or so of replacing the water it quickly starts to turn green. I only have non-exotic fish and a few small terrapins but would like to keep the water relatively clean. I don’t mind renewing the water every month or so, but at the minute it is too regular. I have a pump generating a flow that must oxygenate the water to some degree, but I wonder if there is anything else I can do? I wonder if there is anything I can put in the water that will not harm the fish.

Any ideas?

[bkkmadness]

You get green water in a pond for two reasons, too much light and lots of food for the single celled green algae that creates green water.

Now too much light can be difficult to control in this country, a little shade definitely helps but what you really have to do is cut out the food supply for the algae.

The basic food supply for algae is nitrate, and you get that as a result of fish waste in your pond (it can't be broken down with a standard filter system) and also because tap water often has a high nitrate content so when you are changing the water in your pond unless you know the nitrate content of the pond water and the tap water you don't know if you are helping or hindering the growth of algae.

In fact you should never ever change all the water in a pond of aquarium unless something has terribly wrong, it screws up your filter and it's no good for the fish to completely change their environment every week/month. Though running a little water into the pond to freshen it up once every couple of weeks is worthwhile, especially if you have no real filter system. Just run a hose in there and flood it out a little, but don't go mad and end up replacing all of the water.

You can add chemicals to the water that might help but in general these are not very effective.

If you have a filter you could add an Ultra Violet light system to it which will help but only if you are running a filter in conjunction with your pump.

So one of the best solutions is to cut out that nitrate supply for the algae and to do this you need to add plants to the pond. Plants are a lot more efficient in taking nitrate out of the water and if you have a good growth of plants in the pond they will starve the algae out of there. Take a walk to a natural pond one day, plenty of plants, no green water.

It takes a little while to get the right balance in there but add a few fast growing plant and they will eventually take care of that nitrate problem and algae for you. The natural solution is always the best.

Edited May 19, 2007 by bkkmadness

[TBWG]

How do I stop my pond water from going green? It is a small pond with a little shade from surrounding plants, but after a week or so of replacing the water it quickly starts to turn green. I only have non-exotic fish and a few small terrapins but would like to keep the water relatively clean. I don’t mind renewing the water every month or so, but at the minute it is too regular. I have a pump generating a flow that must oxygenate the water to some degree, but I wonder if there is anything else I can do? I wonder if there is anything I can put in the water that will not harm the fish.

Any ideas?

See following ...should be able to find original post which covers murky ponds

from below dates

TBWG

[.

My pond is natural, about 15m x 25m x 2m. There are some overhanging trees, some lilies, and quite a lot of fish (which I feed).

The pond gets run-off from the raised land for the house, which during rain is sandy / clay pale brown.

Any suggestions from you pond-folk ?

Thanks,

Mike

P.S. I am in Ubon (Isaan)

Right, after consultation with boss lady I can advise that powder is called Bhun Khow ( my phonetic spelling) and cost 5 baht a kilo approx 2 years ago.

I used 2 kilo in a pond approx 30m x 20m and about 2 m deep at the time of treatment, so 1 kilo should be OK for you. I am also advised that it took about 5-7 days to get full benefit. It should be spread as widely as possible over area of pond and not just dumped all in one spot.

Boss lady also tells me it is the powder I sprinkle in the bottom of a hole to prevent disease when I am planting shrubs, mango trees etc.

Hope this helps

TBWG biggrin.gif biggrin.gif biggrin.gif

Thanks TBWG - I will look out for it in the local town.

I have a sneaky suspicion that the name "bhun khow" (your phonetics) might be "baeng khao" (my phonetics) meaning "white powder" blink.gif - on of those highly technical names !!!!

Thanks again,

Mike

I think he is referring to what I would type as "poon khow" which means white cement. They make it up in the mountains by mining a mineral and then heating and grinding it. It is put on some fields to improve its fertility and I believe that is is lime...but I'm only 95% sure as I've never bought any or used any myself.

[thedi]

Poon Kao (gipsum) can be used to bind clay. But this is for muddy brown water. Gipsum binds clay.

If you have green water, your problem is rather algae. As mentioned above, there is too much food for the algae in your water. The best way is to plant a lot of water plants, they use this nitrate and you can harvest the plants and use them as fertilizer in your garden. beside plants like lotus will shield the sun away.

Reduce the fish. There should be not more than 20 cm of fish per m3 of water: all fish in a chain should be not more than 20 cm long for 1000 liter of water. Do not feed the fish or feed them less. Fish food is what you can not use in your water.

I have a pond myself (4 m3) in front of my house and I didn't believe it myself. Until I tried it. Before I never saw a fish three or four days after changing the water: it was green/brown with a visibility of less than 10 cm.

Then I tried it: Filled up about 2 m3 of earth. 30% of the surface is only 10 cm water, 30% is about 40cm and the rest is about 60cm. I planted everything that I found in the shops and 'buengs': Lotus, reed, things that float in the water.

About 80% of the surface is covered with plants.

I have now small fish (up to ~ 5 cm length), at first just enough to keep the mosquito larve under control. There are now a lot of young fish, I guess I have a bit more than 40 cm alltogether now, but nor much more.

When I changed the plan of this pond, I bought a filter system with a pump. It has a UV light in this system, but I switched it on only after about 5 month, when some algae started to grow.

The water in my pond is clear, like water out of a bottle. It really works. But you may have to wait for a month until the system is stable.

Regards

Thedi

[wineman]

How do I stop my pond water from going green? It is a small pond with a little shade from surrounding plants, but after a week or so of replacing the water it quickly starts to turn green. I only have non-exotic fish and a few small terrapins but would like to keep the water relatively clean. I don’t mind renewing the water every month or so, but at the minute it is too regular. I have a pump generating a flow that must oxygenate the water to some degree, but I wonder if there is anything else I can do? I wonder if there is anything I can put in the water that will not harm the fish.

Any ideas?

I had this problem with my small pond, used to drive me crazy with boredom changing the water only to have it go green in a few days.

Acting on advice from someone on this forum, I bought a few water plants (15 Bt each) from an aquatic shop in Theprasit road here in Pattaya. I also bought a product from a similar shop in Third road near TOT. The product is called "MA Plus Algae Control". I changed all of the water, turned the filter back on, put the plants in, also the Algae control and returned the fish. That was two weeks ago and the water has remained very nearly star-bright.

[David2up]

I had this problem with my small pond, used to drive me crazy with boredom changing the water only to have it go green in a few days.

Acting on advice from someone on this forum, I bought a few water plants (15 Bt each) from an aquatic shop in Theprasit road here in Pattaya. I also bought a product from a similar shop in Third road near TOT. The product is called "MA Plus Algae Control". I changed all of the water, turned the filter back on, put the plants in, also the Algae control and returned the fish. That was two weeks ago and the water has remained very nearly star-bright.

Hi,

You mention; "turned the filter back on". What type of filter is this and where within the system is it located?

Cheers,

David

[David2up]

Poon Kao (gipsum) can be used to bind clay. But this is for muddy brown water. Gipsum binds clay.

If you have green water, your problem is rather algae. As mentioned above, there is too much food for the algae in your water. The best way is to plant a lot of water plants, they use this nitrate and you can harvest the plants and use them as fertilizer in your garden. beside plants like lotus will shield the sun away.

Reduce the fish. There should be not more than 20 cm of fish per m3 of water: all fish in a chain should be not more than 20 cm long for 1000 liter of water. Do not feed the fish or feed them less. Fish food is what you can not use in your water.

I have a pond myself (4 m3) in front of my house and I didn't believe it myself. Until I tried it. Before I never saw a fish three or four days after changing the water: it was green/brown with a visibility of less than 10 cm.

Then I tried it: Filled up about 2 m3 of earth. 30% of the surface is only 10 cm water, 30% is about 40cm and the rest is about 60cm. I planted everything that I found in the shops and 'buengs': Lotus, reed, things that float in the water.

About 80% of the surface is covered with plants.

I have now small fish (up to ~ 5 cm length), at first just enough to keep the mosquito larve under control. There are now a lot of young fish, I guess I have a bit more than 40 cm alltogether now, but nor much more.

When I changed the plan of this pond, I bought a filter system with a pump. It has a UV light in this system, but I switched it on only after about 5 month, when some algae started to grow.

The water in my pond is clear, like water out of a bottle. It really works. But you may have to wait for a month until the system is stable.

Regards

Thedi

Hi Thedi,

Could you please pass along the info on what type of pump-filter system (media) and where did you buy this and the approx cost.

And if anyone is interested here's the address of a good site regarding algae control <www.skippysstuff.com/fmbest.htm

Cheers,

David