Ok, here is teh challange:
- pond was leaking
- filters are off
- water was staning while it was being fixed for about 10 days
- hardly any water circulation no UV light

Pond is green, visibility about 40cm, 25 little koi that are in now very happy.

Since Sunday morning, filter working 100%, UV light on and happy.

How long should I wait to see if it clears before taking other measures?

what size UV do you have on there??

If it's just 1 x 55w then I would have to say about a week before visibility increases. Do you have any flow movement in your pond? I reckon if you had to circulate your water this way you would have your water circulating towards\around your drains which would help in turning all your water over which would probably help with regards to the clearing up process.

Just me from personal experience, there could be an easier way. Also think there's the clay option which sort of works as a floculent where it will settle all to the bottom which will then eventually get sucked up, think for this option current\flow would be a bad thing as the water needs to be absolutely still for this.

The water is being taken out by 3x 110mm bottom drains, going through a massive e-clear water station with a 55w UV light of about 70cm.

There is plenty of water movement with 1 input via the 0.75kW pump

would adding a UV help? looked at the flow rate max for a 55W is 300l/m the pump is pushing around 15000l per hour or 250l/m

Another UV will help but is it really worth it, only to get the system clean sooner. A 55watt UV is good enough for your system.

I would add a lot of salt (3kg / 1000 liter) which will speed up the process dramatically. Because you have a new pond, it is good to have a lot of salt in there anyway. It should be clear within 10 days. Also add a bit of bioboost.

Hmm that is 3x48 around 150kg, have added 100kg already will add another 50kg tonight........thanx for the tip!

I think Paul's salt idea is a good one. I had horrible green water and added 3 x 55W UV’s on a 30kL pond.( running in parallel to split water flow and to have less restrictions) Cleared water within a week or so.

8 Weeks ago I switched them off but must admit I increased the salt to 0.38% due to health problems. With all the water changes the salt level came down to 0.12% now, and water still crystal clear.

I would, talke the cautious natural route.
Make sure filters are clean, ie no sludge at the bottom or dead rats

Do weekly flushes, and the nleave it be for 3 odd weeks.

These things take time. Nothing good happens quickly in fish keeping.

My penny’s worth.
The water contact time, flow rate plays a major role in the effectiveness of your UV light. Check your manufacturers recommended flow rate per tube. Personally when pushing more than 12000-15000 L per hour I would split the pipe work before the UV to give more water contact time in UV for more effectiveness. Bulbs needs replacing every 5000 and 8000 hrs or between 8 and 12 months.

Hi,

I would like to state the following; a UV light is an illusion!
It will not work when there is an alga bloom in your pond. The alga is the green stuff in the pond, which is responsible for the green water.
Algae are a “plant” and during the night, not only are they using up oxygen, but they are also releasing carbon dioxide as a by-product of respiration ( as do fish). This carbon dioxide is very water-soluble, forming carbonic acid.
Therefore during the day, as the plants photosynthesize, carbon dioxide and even bicarbone irons are removed from the water are which, in turn causes an increase in pH, reaching a peak shortly before sundown.
Ponds experiencing extreme algal blooms may be subject to super-saturation of the water with oxygen during the daylight hours.
Back to the UV light.
Inside the unit is a fluorescent tube radiates ultraviolet (UV) - short wave length light at the far end of the purple-blue region of the visible spectrum.
UV lights are harmful to living tissue and at the right concentration will disrupt the cell contents of the algae, causing them to collapse and decay.
It is important here to make a distinction between an UV-clarifier and an UV-stariliser more commonly used in tropical freshwater and marine aquarium hobbies.
The clarifier will affect just the green alga’s cells, while the steriliser( which has a higher light output as well) is designed to control some bacteria and parasites in the water.

So, for a UV light to work we should look at a few things.
As algae reproduce at a rapid speed, the UV light will not be able to control it, without the proper filtration system.
Water changes is essential.
The fluorescent tube of the UV light should be clean regularly (every two months) and replace every 12 months. If the tube is not clean, the light output will fall dramatically with no effect.

In my opinion is a UV light a waste of money!

All we need to do is to kill off the algae and the remove the debris through water changes and an effective filter system.

Salt may work, but by using Potassium Permanganate (KMnO4) you will be able to break down algae and organic material abounds in the pond.
A dose of 1,5g per 1000lt will do the trick.
A 20% water change after three days of the dose, with 10% water changes every second day until water is clear.

and the fish? Would they be ok with that dose? How tolerante is the dose, as the pond volume is very difficult to calculate.

ok, and if I am not that patient? How about added some of those algae additives? Any suggestions recomendations which one to use or not to use...?

PP?
What about the good algae, ie the algae mat that you want to have growing in your pond?

Also do you bypass your bio filter?

PP kills everything. it does not discriminate between good and bad.

I avoid adding chemicals, i beleive the pond has to find its natural balance, a pond must be a balanced enclosed, ecosystem?

If the water is alive the fish are happier and healthier,

PP kills the water.

water goes through 3x 800l filters, 1st one is a settlement chamber with 6 brushes, then 2x chambers with filter media......

David,

I really would like to see dead water! It should smell awful!
Algae on the walls of the pond are “good” algae, not the floating algae causing green water.
The “good” algae will be back within a week after the PP has been flushed out, through water changes.

PP will not “kill” the bacteria in your filter at that dose, I dosed up to 4g per 1000lt, with no effect to my filter at all.
If you have an alga bloom, it will cause more problems to your Koi, then by using PP!

I am using PP after every Winter on all my ponds, never lost a Koi or had any problems with my filter systems.

Do not believe everything you heard from the so-called experts, listen to the people with experience!

Looks like you are not able to bypass your filters during a PP treatment, and therefore I will not use PP to kill algae, even at a 50% dosage suggested by Pieter.

You will get clear water from the PP treatment/s, but you will purely postpone the balance/maturity required to maintain clear water, PP puts the fish under unnecessary stress and you will kill off some good bacteria (Nitrosomonas and Nitrobacter) needed to develop the balance.

yes, can't bypass the filters. Think will wait for a while.

has anybody got experience with Viresco? Worth the money?

[quote="Pieter J de Villiers"]Hi,

Ponds experiencing extreme algal blooms may be subject to super-saturation of the water with oxygen during the daylight hours.
Hi Pieter
I have a 25000lt pond and i think very good filteration(settlement chamber,vortex 1 with brushes,vortex 2 with matala matting and brushes,vortex 3 with kaldenes media,all 3 vortex have air difusses,thereafter 2 bead filters,2 uvs 55 watt each,a .75 speck,a protein skimmer and a 50 lt booster at the end,i also have 2 air difussers in the pond) .i have a 120lt hakko air pump that drive all my air difussers and my pond really bubbles.
My problem is i do not have crytals clear water always looks murky.
Is it that mt water is super saturated with oxygen?
Ido weekly water changes 10 to 15 % Thanks

Hi
Have used viresco and my algae on waterfall turned brown and did die off,however the fish seem to be more active and hungry.
Viresco is expensive R360 for 10g to treat 25000 lts avalable from Happy koi. very good product
Anver

access oxygen is a good point

“Bull”or rather WP!

Firstly, PP is only active for about four hours, as soon as it turns brown it is not active anymore.
If you, like me has sand filters, you bypass the sand filter during the four hours. As it turns brown, run it through the sand filters, your water will be crystal clear after about six hours, in total ten hours to clean your water.
Certainly the algae will be dead, that’s what we want to get rid of ...........hello!!!
New flash.................Nitrosomonas and Nitrobacter don’t die that easy!
Let us talk about stress on Koi.
When can you establish that Koi is stressed?
One way is to look at the white area on the fish, if it becomes “pink” then surely the fish is stressed! ( When catching fish this happens most of the time)
Now, how do you establish the grade of stress inflicted onto Koi, looking at a scale between 1-10?
Let us say, that when the white on the fish is "pink", the stress is 10, and if there is no indication of stress ( no fish darting away in the water or jumping out of the water) it is zero. What is the stress level measured against PP or an alga bloom for that matter? Even an attack by a predator?

What I am saying is that the fish is stressed anyway, during some algae bloom!

Anver;

No, I would think it is cause by over feeding. I would ad a sand filter to the system just before entering the pond, to polish your water.

PS. Remember the opening posting by Adi................ “Green water Challenge”

A dose of 1.5g per 1000L is very, very low. It will first attack the floating algae and will be exhausted before it gets to your filter and it being a new pond I don't think it is a bad idea. I have seen it used by Japanese breeders in newly harvested ponds for many years.

a New pond can be hard on koi and if you are unable to see them you will not notice any problems until too late.
Viresco is also a chemical and I am sure lingers for longer in your system.
I suggest getting a bigger UV light.

Pieter J de Villiers wrote:

David,

I really would like to see dead water! It should smell awful!
Algae on the walls of the pond are “good” algae, not the floating algae causing green water.
The “good” algae will be back within a week after the PP has been flushed out, through water changes.

PP will not “kill” the bacteria in your filter at that dose, I dosed up to 4g per 1000lt, with no effect to my filter at all.
If you have an alga bloom, it will cause more problems to your Koi, then by using PP!

I am using PP after every Winter on all my ponds, never lost a Koi or had any problems with my filter systems.

Do not believe everything you heard from the so-called experts, listen to the people with experience!

Hi, I hear you Pieter.
I personnaly do not like using chemicals and if i do then there must be good reason why it is done.

So hopefully if i have achieved nothing else , at least i have achieved debate around this topic, and people will have learnt to think out what they are going to do and why?

Thats all.

There is no one way to fix this.

thinking of the 1.5g per 1000l. Should still have left from disinfecting plants.

Jaco wrote:

A dose of 1.5g per 1000L is very, very low. It will first attack the floating algae and will be exhausted before it gets to your filter and it being a new pond I don't think it is a bad idea. I have seen it used by Japanese breeders in newly harvested ponds for many years.

a New pond can be hard on koi and if you are unable to see them you will not notice any problems until too late.
Viresco is also a chemical and I am sure lingers for longer in your system.
I suggest getting a bigger UV light.

I thought it was a natural bacteria, not a chemical?