***The Pond Discussion Thread****

Soldato
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Im surprised that you need anywhere near as much as that thiosulphate to neutralise fresh water. I use it at work if I'm trying to sort out a customer's swimming pool/spa that they've overdosed with chlorine and rarely would use that much, even on much bigger swimming pools with free chlorine readings over 10ppm. I would have thought 100g would be more than enough, and not have as much of a negative effect on the pH levels

Well that was the output from a koi site calculator. I have two 500g bags so I don’t need to use it all and I can test the chlorine level. Koi aren’t sensitive to it plus it’s used for Potassium permanganate overdoses should I get a measurement wrong.
 
Associate
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Well that was the output from a koi site calculator. I have two 500g bags so I don’t need to use it all and I can test the chlorine level. Koi aren’t sensitive to it plus it’s used for Potassium permanganate overdoses should I get a measurement wrong.

Obviously my experience with it is solely on swimming pools/spas/hot tubs and not ponds so I'm not saying you're dosage rates are wrong, just that I'm surprised by the amounts required.
 
Soldato
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Obviously my experience with it is solely on swimming pools/spas/hot tubs and not ponds so I'm not saying you're dosage rates are wrong, just that I'm surprised by the amounts required.

good to have an independent point on it though. I’ll go back and ask on the forum.
 
Associate
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Got up this morning to a dead koi, plus x2 others on their side (not dead yet, netted them and have the aerator blowing up onto them, to see if they can be rescued - checked inside the gills, all clear).
Checked the water, all ok.
Cleaned the filter out just in case (it wasnt dirty at all).
Done a 20% water change.
Trimmed back all foliage (there were some decaying foliage, maybe there was something there poisonous to them?).
Vacced quite a few dead leaves from the bottom of the pond.

Baffling, had this pond for over 5 years without a hiccup :-(
 
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Soldato
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Did you have a power cut during the night?

If it was oxygen they’d be gasping for air or rising for air. Electrocution can cause fish death and neural injuries. The same with poisoning.
 
Associate
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I have been out and bought a pondlabs multitest kit for the water, and have found a couple of problems:
Readings as follows:
PH 6
Nitrite between 0-0.25
Nitrate 40
KH 125
Ammonia 0.5

I am slowly doing a water change to bring the ammonia and nitrate back inline (will keep doing that over the next few days, the pond holds 22,000 litres).
Will a water change also help with Ph? (read online that I can add baking soda if it doesnt, but I am a little nervous about that tbh).
There was a lot of dead foliage around the pond = cut all of that back / dead leaves in the bottom of the pond, removed those - hoping that will help reduce the ammonia.
Not feeding the fish, obviously.

The x2 fish that were on their side are still in the separate nets with the aerator blowing over them.

Any other ideas?
I have been away on holiday and then have been working away.....didn't think it would go downhill this fast (never has before, but then again I didnt have the multitest kit, only a single Nitrite test (which was always ok).
 
Soldato
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Hmm puzzling - how are the remaining fish?

Spent the day today sealing the coping stone cement with exterior paint outsize and mastic pond sealant on the inside. Once it's cured, I have to wash down the walls, pump out the cement laden crappy water, and start the fill.. Still got a few odd jobs but for now there's not much I can do.
 
Soldato
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Spent today cleaning and draining. Looks better when there's no cement smearing on the walls.

hPZYoqd.jpg


Tomorrow I'll sort out some of the final gluing (bottom drain aerator and a couple of filter pipes) and cleaning of the rear chamber floor.

Then it's fill time.

Ignore the mastic - there's a blade task when the weather warms up again along with another layer of paint.
 
Soldato
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Ponds outside need some sort of lid in the winter. Ponds/lakes/streams get destroyed if they are in the open. Even worse if a cormorant sees the open water.

The original pond had over an inch of ice in -17degC before. All fine. From a fish perspective, as long as the fish can drop down deeper and the pipes aren't going to freeze then all is good.

Herons and other preditors are naturally drawn to ponds as winter closes in.
 
Associate
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Looks good Nick.
I have never had a problem over Winter tbh - due to the pump cirulating the water fairly quickly and the aerator permanently on, it has never frozen over.
My filter is at the other end of the garden in a shed, with all of the pipework sunk under the lawn.
I currently have a net over the top, to stop falling leaves from surrounding trees and the pesky heron from going into the pond.
 
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Associate
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I will do another water test this morning, to see if the ammonia and nitrate have come down sufficiently.
Lost x2 fish in total, managed to rescue the 3rd, which is now dormant (but alive) at the bottom of the pond
 
Associate
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Just done another water test and the ammonia and nitrate is still too high.
I am currently doing a 50% water change to bring that down quickly.
Been a bit baffling why the sudden spike, must be something linked to me been away for a few weeks, so it was left unmonitored.
 
Sgarrista
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125 for KH? This isnt a standard test number.


Much too low.


At a guess you have had a KH induced PH crash which has turned your water into acid.

Buy a tub of Hexeal SODIUM BICARBONATE | 10kg Bucket for 15 quid, and chuck a scoop in each day to slowly bring the level up and maintain a high KH and healthy PH. As a baseline I chuck 20 grams in per day (a whey protein scoop) and my pond is 4000 gallons of water or so when you include the filter and pipework.

Once your PH has slowly been bought back to 8.5 you cant overdo the bicarb, so just keep maintaining the scoop a day. Koi will happily live in 8.5 PH water and the high KH will prevent PH swings and also give your filter bacteria a lot of the stuff they need to do their job more effectively.
 
Sgarrista
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7dkh
PH is now at 7

7 dkh is a healthy number as is 7ph, still flirting on the low side of PH for my personal liking as it wouldnt take much to drop that down again.

Your pond, your call, personally chucking in a maintenance dose of KH every day is cheap and highly effective way of keeping a pond healthy imho. I run 12dkh and PH 8.3 on the nose all day every day (the max bicarb can take it to, if you add more after this is acts as a buffer in both directions and is completely harmless).

A 10kg bucket of bicarb lasts me 18 months, so for 15 quid its a no brainer.
 
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