Salt how much/how long is enough

[RayJordan]

Lots of information, some good - some bad, on the web about the use of salt in koi ponds. I had someone call me that had been having a running battle with ulcers on their koi. They had tried everything reccomended on the message boards except getting a scraping under a microscope to determine what type if any parasites their koi might have. I figure they spent enought on meds to buy several scopes.

After buying an entire fish pharmacy and dumping it all into their pond they were not seeing any new ulcers but the old ones were just not healing. I made a pond visit and the usual water tests seemed OK. I scraped and found no paracites (which wasn't surpising considering all the different treatments they had tried). There were some nasty looking ulcers on several koi that I was told had been there for months.

Next we caught the koi with ulcers and I noticed they felt like sandpaper. No slime on these koi at all. After showing them how to clean, treat, and seal the ulcer of the first koi I watched them treat the rest. Then I tested the water for salt. It tested at 0.8%. They had though they were adding enough salt to get to 0.3% after water changes but did not have a salt test kit and I think their pond volume was much less that their contractor had told them. I had them do a 50% water change that same day and another 50% a few days later. I had them buy a salt test kit and told them not to add any more salt and let routeen water changes flush out the remaing salt.

It has been about three weeks since my visit and they just called to say all the koi were healing nicely and no new problems had occurred.

Salt is not a harmless tonic. It will definately inhibit wound healing if used at too high a dose(above .3%). It will hurt your biofilter and kill your ponds algae coating and cause a major crash in water quality as a result of rotting dead algae.

Use salt for a short period of time for a specific purpose.
0.05% to 0.1% to reduce stress (few days to 2 weeks)
0.3% to 0.6% for a treatment of protozoan paracites for (two weeks max)
be very careful about using salt in combination with other water treatments.

If you use salt you must use a salt test kit to insure you are getting the right dose.

[koiczar]

Great post Ray. This is very valuable info, especially for newbies or general ponders. Lot's of bad info about the use of salt, as well as other more dangerous medications, as a cure-all out there that can mislead people. Shot gun treatments are not the right approach. Find out what to treat for and then treat. That's the key to success!

Mike

[saratogatan]

This is a great post, ray. Like mike said, I think the flood of 'fix all' poison is partly to be blamed for the problem. In many situation, the hobbyies should also bear some responsibility in taking the 'easy way out' of dumping in the 'fix all' poison.

since people of all walks are in this hobby, we cannot prevent tragedy from happening. If anything is to be done, I think koi joins are the starting point. Theorittically, it shoudl work like this :
- customer pick koi
- koi operator ask :
- do you have water testing kit ?
- what is your pond setting ? filtration, size ?
- how many koi do you have, and plan to have ?
- how often do you do water change and filter cleanup ?
- do you have a good net and tub ?
- can you net you koi from your pond ? (most will say 'piece of cake', but we need to ask anyway)
- do you know salt and its relation with koi keeping ?
- do you know how to cleanup wound/ulcer using PP, H2O2, and dress it up with medication ?

I know there are a lot more question to be asked. However, by starting at some basic questions, a koi join operator can easily determined if someone is ready for koi. If he/she has the good intent, the hobbyist can learn to start in the right direction for a happy hobby.

When we started this hobby, only 1 place asked about the size of our pond, the other ask about the filtration. Everone wanted us to buy load of koi. I have paid dearly learning things I did not learn when we got started, and my back is hurting thru the learning process.

stan

[kingkong]

Do you think the irritant was the meds or the salt that put these fish in a situation which was beyond their tolerance level, depleting their ability to produce enough mucus or slime coat? Salt or irritants will cause koi to increase mucus but eventually can run slime production dry, resulting in sandpaper skin.

[RayJordan]

Quote: Originally Posted by kingkong Do you think the irritant was the meds or the salt that put these fish in a situation which was beyond their tolerance level, depleting their ability to produce enough mucus or slime coat? Salt or irritants will cause koi to increase mucus but eventually can run slime production dry, resulting in sandpaper skin.

I have seen salt alone strip off the slime layer if used at high enough dose and for long periods. The slime coat will rebuild if the salt level is reduced. But if salt is maintained at high levels over a long period of time slime producion fails and eventually the fishes kidneys will fail also. Salt plus lots of meds is asking for trouble.

High levels of salt will actually prevent wound healing. I learned this years ago when I had tried everything to get a ulcer to heal on a koi that just would not. I was told to do water changes to reduce salt from 0.3% to less than 0.05% and without doing anything other treatments the ulcer healed quickly.

[Regenmeneer]

Great post everyone!

Salt will activate production of slime coat because it burns off the old layer.

Not sure if zeolite is being used in other parts of the world? But when using salt in higher concentrations, make sure to remove all zeolite as it will release all amonia stored inside!

Regenmeneer

[kingkong]

OK, the staement 'salt will activate the production of slime'. Is it because the fish reads the extra salt percentage as a irritant? Is it because the osmoregulation balance has been changed?
Another idea or concept that I can't figure out is 'salt strips the slime coat off' or "salt burns off the older layer'.
A freshwater fish's osmoregulation provides a selective interface to maintain internal/external ionic balance. Fish constantly urinate as their bodies are 'saltier' than the water around them. The slime helps keep the balance. Now, why is adding more salt in the water going to 'strip off the slime coat'? You would think the fish would enjoy the fact it doesn't have to urinate every 5 minutes.

[saratogatan]

I like to invite REC to enlinghten us a litle.

REC, are you out there somewhere ?

stan

[kingkong]

I think I got it. Things that trigger cell hyperplasia (abnormal increase) or muco-stimulation in fish. First some boring stuff.
Osmoregulation is the control of the levels of water and mineral salts in the blood. This is important because the fish cells are being bathed in tissue fluid which has the correct amount of water. It is a homeostatic mechanism. Homeostasis is the maintenance of constant interior conditions. VERY important that the fish tissue does not lose or gain water by osmosis because the concentrations of water and salt is the same inside and outside the cells.
Then it got more fun. Most freshwater fish (koi), do not have the physiology to deal with salt being added to their water. What! Their kidneys and other organs have evolved thousands of years to work perfectly in their environment. When a fish is placed in water with salt added, the fluid within the fish still leaves (urinate), then begins trying to get rid of excess salts but can't. The fishes' body evolved to hang on to salts, not get rid of them. This actually causes the fish to dehydrate. The result is stress on the fish.
I thought I had it. Well wait. If the skin on a fish is virtually impermeable with its mucous coating, the hyperplasia of the slime coat would not be in gaurd or protection of osmoregulation, the fish must feel this NaCl as an irritant.
Most all the osmotic entry of water and diffusional loss of salts is happening at the oropharyngeal cavity and the gill epithelium anyway.

[Russell Peters]

As much as possible and as long as you can possibly....... oops your talking about salt. Sorry