Green Slime In The Pond

[tim armstrong]

Well now that we have finally restored our pond, by the addition of more concrete lining, which seems to be working, there is a new problem -the green slime. Depending on your viewpoint this stuff either looks like pureed spinach or green vomit. It covers most of the surface of the 25m X 11m area but hasn't affected the few lotus plants we've started to put into it. We've also added some water chestnuts ? the ones that produce the buffalo horn shaped vegetable. I skim it with a net daily, but its not making much impact.

The in-laws have finally given up on a chemical solution, so I'm wondering if there is a green slime eating fish,or plants that will clear it. Being wet season, the water is quite warm so everything grows. We have also treated it for mossies, which has worked. There are no fish or any other animals in it yet, except for a large but thin monitor lizard, who didn't find any fish or take to the slime, - so he's now left.

All suggestions much appreciated.

[sawati]

I have the same problem in Bangkok.It begun maybe 1 year ago?...Before i dont had this problem

[ozzydom]

Heavy algae growth is normally the result of a heavy concentration of nitrates getting into the pond.

Is there any way that fertilizer has found its way in,? run of from paddies will do it as farmers use 46% Nitrogen on their rice, this can also come from bore water as the fertilizer gets down to the water table.

Pumping the pond down and replenishing from a clean water source will help.

Pla Nin (Nile Tilapia )feed on algae so a couple of hundred of these would help.

Oxygen levels can be depleted as a really heavy algael bloom prevents the entry of light.

If the pond has an overflow outlet,a lot will go as you pump in fresh water.

[tim armstrong]

Heavy algae growth is normally the result of a heavy concentration of nitrates getting into the pond.

Is there any way that fertilizer has found its way in,? run of from paddies will do it as farmers use 46% Nitrogen on their rice, this can also come from bore water as the fertilizer gets down to the water table.

Pumping the pond down and replenishing from a clean water source will help.

Pla Nin (Nile Tilapia )feed on algae so a couple of hundred of these would help.

Oxygen levels can be depleted as a really heavy algael bloom prevents the entry of light.

If the pond has an overflow outlet,a lot will go as you pump in fresh water.

Thanks Oz. No fertilizer that I know of, and no paddies nearby. But we filled it after the restoration work was completed from a bore next to it. plus rainwater over the past few months. It doesn't get much runoff. The bore water is very good generally, maybe a bit alkaline. Pla Nin sounds like a good idea. We might try a few more plants and soil, and let nature restore the balance as well. Thanks again.

[IsaanAussie]

I had the same problem. Broadcast lime on the surface, pump the water to oxygenate and spray 1::1000 EM on the surface.

My problem caused by black water from pigs septic system. Shock killed those fish (I wasn't aware they were in there) that dont do well in green water ponds

Isaan aussie

[WatersEdge]

If it is Duckweed,

tiny floating plants that multiply very rapidly

then fish will eat and do well on it,

and if you skim it off the surface,

it's good animal feed as well.

Skim it off, dry it a day in the sun,

and feed it to chickens.

Or just compost it as very good fertilizer.

Amazing that bore water would bring an instant plant bloom.

I'm sure plenty of farmers would like to have your magic water.

and of course I'm curious what the water analysis shows.

[Crushdepth]

You probably have an over supply of nutrients. Potential solutions include avoid adding organic matter or fertiliser to the pond, do partial water changes occasionally, and/or add algae-eating fish species. Tilapia are a good choice.

[rodcourt49]

I had the same problem. Broadcast lime on the surface, pump the water to oxygenate and spray 1::1000 EM on the surface.

My problem caused by black water from pigs septic system. Shock killed those fish (I wasn't aware they were in there) that dont do well in green water ponds

Isaan aussie

..some Aussie cockies used to chuck in a green hay bale..this also caused a neutralising effect and alien bacteria that fed on the weed. From memory 'alum' powder can cause some toxic result..I realise you only have a small pond but some cut rice stalks may also do the trick..this may help

[IsaanAussie]

I had the same problem. Broadcast lime on the surface, pump the water to oxygenate and spray 1::1000 EM on the surface.

My problem caused by black water from pigs septic system. Shock killed those fish (I wasn't aware they were in there) that dont do well in green water ponds

Isaan aussie

..some Aussie cockies used to chuck in a green hay bale..this also caused a neutralising effect and alien bacteria that fed on the weed. From memory 'alum' powder can cause some toxic result..I realise you only have a small pond but some cut rice stalks may also do the trick..this may help

Well actually this Aussie didnt need to chuck any in, deed done by a grazing buffalo for me. Two bales of rice straw went in a couple of months ago. Thanks for the tip though, I may try that in future. Come to think of it the water did seem a little clearer afterwards.

[JurgenG]

We had the same problem. We used a rake with an extended handle (around 4 m long) to clean the pond and threw in a few hundred fishes as Ozzydom advises.

So far so good ....

[ozzydom]

Horses for courses, we actually add triple super phosphate to get the effect that you have Tim ,if no more nutrients find its way into the pond it will clear naturally ,as the algae need it to survive.

Seepage affected by household runoff (grey water) will also cause algael bloom as household detergents etc contain huge amounts of phosphates.

[Sparkles]

Algae is at its worst in the rainy/humid season expect it to improve with the cooler weather.

[tim armstrong]

Update: Thanks guys, interesting suggestions. I'll try the fish and the water changes and maybe the bale of rice straw and see what happens. I spent a day skimming with the long handle method recently, but could hardly see where I'd been an hour later.

Aha moment! Just maybe the nitrate is coming from the paint my wife put on the inside because she didn't like the concrete colour ! I'll keep you posted. Regards

[Scully]

We went to a government run fish farm in Udon Thani and ordered 1000 fish for our pond as pig overspill was having the same effect. The fish came to a grand total of 300 baht but you have to grow them in a large net in the pond so no other fish can eat them, once they are the size of two of your middle fingers you can let them go.

The pond is now clean as a whistle and if we feed the fish they can be sold at market in about 8 months, however I am quite happy that they just eat the excess kee moo.

[ozzydom]

We went to a government run fish farm in Udon Thani and ordered 1000 fish for our pond as pig overspill was having the same effect. The fish came to a grand total of 300 baht but you have to grow them in a large net in the pond so no other fish can eat them, once they are the size of two of your middle fingers you can let them go.

The pond is now clean as a whistle and if we feed the fish they can be sold at market in about 8 months, however I am quite happy that they just eat the excess kee moo.

A word of advise Scully, the mesh of your hapa (net) will block up easily and should be scrubbed once a week or you may see 1000 fry gone to fishy heaven one morning due to oxygen deficiency.

Scrubbing with fry in situ is awkward so an alternative is to set up another hapa to transfer the fry into while the dirty one is removed for cleaning.

[tim armstrong]

Further update : So far have not done anything, because of extremely heavy rain for the last week. Maybe the overflow or the rainwater restoring the balance, but it has started to look cleaner, - a bit. Now still raining so we'll see. Unbeknown to me the brother in law has also started to add small fish to it that are too small to cook. Regards.

[IsaanAussie]

Further update : So far have not done anything, because of extremely heavy rain for the last week. Maybe the overflow or the rainwater restoring the balance, but it has started to look cleaner, - a bit. Now still raining so we'll see. Unbeknown to me the brother in law has also started to add small fish to it that are too small to cook. Regards.

Tim,

You will get your answer on balance on the first sunny day. Yesterday for me was that day and the algae bloomed again. Light rain last night knocked it down again and the fish are very active. IMHO, do nothing other then watch for changes.

IA

[tim armstrong]

Further update : So far have not done anything, because of extremely heavy rain for the last week. Maybe the overflow or the rainwater restoring the balance, but it has started to look cleaner, - a bit. Now still raining so we'll see. Unbeknown to me the brother in law has also started to add small fish to it that are too small to cook. Regards.

Tim,

You will get your answer on balance on the first sunny day. Yesterday for me was that day and the algae bloomed again. Light rain last night knocked it down again and the fish are very active. IMHO, do nothing other then watch for changes.

IA

IA, - You were right. The sun came out for a few hours this morning, closely followed by the slime. But more rain forecast. I'm now looking for some rice straw and fish. Haven't seen the goanna lizard thing lately, maybe he'll discover the fish - bugger!. Isn't it great to watch nature at work ? I remember seeing a doco somewhere about the green algae. Apparently it's the fastest growing organism on the planet

[Tigs]

Apparently it's the fastest growing organism on the planet

And I believe is crucial to our survival as it produces as much oxygen as the Amazon rain forests.

Regards the algea eating fish Pla Nin (Nile Tilapia ) can you keep these kind of fish with Koi Carp? I have a water feature with a tiled sides and bottom and we had nie carp in there that were doing well, however even after buying expensive filters the water and tiles would become quickly covered in Algae (after 8 days you could not see into the water. I bought a chemical to control algae , which if used properly was safe, however my brother in law took it upon himself to treat the water whilst he was pi**ed, and poured the whole bottle in and killed all of my lovely fish:angry: However, before I embark again I am looking for a better solution, the Tilpia sound good, but would the larger Carp eat them?

[tim armstrong]

Apparently it's the fastest growing organism on the planet

And I believe is crucial to our survival as it produces as much oxygen as the Amazon rain forests.

Regards the algea eating fish Pla Nin (Nile Tilapia ) can you keep these kind of fish with Koi Carp? I have a water feature with a tiled sides and bottom and we had nie carp in there that were doing well, however even after buying expensive filters the water and tiles would become quickly covered in Algae (after 8 days you could not see into the water. I bought a chemical to control algae , which if used properly was safe, however my brother in law took it upon himself to treat the water whilst he was pi**ed, and poured the whole bottle in and killed all of my lovely fish:angry: However, before I embark again I am looking for a better solution, the Tilpia sound good, but would the larger Carp eat them?

There should be a separate thread on p**ed brother in law experiences. Mine is an expert at weed control with the sprayer. When pissed he takes the scattergun approach and walks in random directions all over the place. Funny how orchids and expensive frangipani trees don't appreciate it much.

[IsaanAussie]

I had a surprise visit from the boys from the Amphur Office who came to investigate my pond. It had a bit of algae on it but it was a beautiful shade of emerald green. The complain came from a jealous neighbour who for some reason thinks I am getting rich, silly man. Anyway, the guy in brown with the shoulder stripes speaks some and understands a lot of English so conversation wasnt to hard. The complainant hobbles over and says his family is sick because my pond water is affected them.

What says Khun Stripes, not from this pond, this is very healthy, look at the fish. No your problem is coming from that slime hole over there with the mangy ducks swimming on it, go and compalin to the owner.

The conversation stopped as Khun Jealous spun on his heel and went home to feed his ducks.

What can you say? Fancy a beer Stripes my old mate?

Isaan Aussie