Wednesday, May 30, 2007

Should I have a constant concentration of salt in the pond? If so, what concentration? -Glenn

The only time salt is absolutely needed is when your Koi have a parasitic infestation. Salt hurts freshwater parasites because they are used to living in a saline-free environment. Salt irritates Koi, so it makes them produce a thicker slime coat. Some people keep a low level of salt in their ponds to help their Koi osmoregulate too.

From the Wikipedia article: Osmoregulation is the active regulation of the osmotic pressure of bodily fluids to maintain the homeostasis of the body's water content; that is it keeps the body's fluids from becoming too dilute or too concentrated. Osmotic pressure is a measure of the tendency of water to move into one solution from another by osmosis. The higher the osmotic pressure of a solution the more water wants to go into the solution. The pressure that must be exerted on the hypertonic side of a selectively permeable membrane to prevent diffusion of water by osmosis from the side containing pure water.

Animals in all environments (aquatic and terrestrial) must maintain the right concentration of solutes and amount of water in their body fluids; this involves excretion: getting rid of metabolic wastes and other substances such as hormones which would be toxic if allowed to accumulate in the blood via organs such as the skin and the kidneys; keeping the water and dissolved solutes in balance is referred to as osmoregulation.

If you want to keep a low level of salt, add one pound of rock salt per 100 gallons of water.

Koi in Aquarium

I would like to have Koi in an aquarium. I'm getting a 29 gallon tank and filter along with other stuff since I don't have a pond or have the money for it. Is there anything else I need to do to keep them healthy? Like vitamins? -Sydney

Just make sure that you have adequate filtration on your tank and you feed them a good Koi food. Maybe plan ahead and find someone that could take them if they outgrow your tank.

Worming Koi and Bottom Drains

Q1. I recently overheard a conversation about worming Koi fish at least once a year. I cannot find anything about this on the web, is this a normal practice and how or what do you use to do it.

Q2. I am shortly starting construction on a 6,000L pond, concrete floor and brick walls sealed with a pond sealer. My question, is it worthwhile putting in bottom drain in a pond of this size. Thank You. -William

I suppose that the people that were talking about worming Koi were talking about Flukes. Flukes are microscopic parasitic worms. Usually you can get rid of them with salt and Potassium Permanganate.

It is definitely worthwhile putting in a bottom drain. Anytime you have something that will automatically remove Koi waste and other debris from a pond, it is a good idea. There are even bottom drains that have built in aerators.

Small Pond, Large Koi?

I am only 20 years old and very new to the world of the Nishikigoi and becoming extremely interested in this hobby. I am worried about the size of my pond (only 90 gallons). How many Koi under 12" can this comfortably support??

and also...Could it support Koi larger than that until next year when
I have the money to work on a new pond? Any tips to help would be
much appreciated! Thanks! -Tweek

Your pond can probably support 4 to 5 small Koi, for a while. Eventually they will outgrow that size of a pond and will need a bigger area to live in. I would not get any Koi that are larger than six inches until you get a bigger pond. Larger Koi need more water volume, more aeration, more filtration, ect. You will run into problems with putting large Koi in a small pond.

I have lost two fish who seem to have dirt or old food coming out of thier gills? What caused this? -Dave

That dirt or old food is probably a fungus. A fungus is a secondary or tertiary infection. It basically means that something damaged your Koi and its immune system was weakened, so the fungus was allowed to take over. You need to find out what caused this and then take the appropriate action.

Friday, May 18, 2007

I have two Koi, the smaller slender one always swims under the larger rounder Koi. Why? -Phyllis

Koi aren't really anywhere near the top of the food chain, so they will do whatever it takes to not get eaten. Your smaller Koi probably feels safe while hiding under the big one. Maybe he will be more friendly if you put some more Koi into your pond.

How do you tell the sex of a Koi fish? -Angie

There's a great article about it here, Sexing Koi.

Do Koi fish die after giving birth like salmon? -Angie

Koi do not die after "giving birth". Koi don't actually give birth, they are egg layers. The females release their eggs and the males then fertilize them. When they reach sexual maturity, they are able to spawn every year for the rest of their lives. Most people find this out the hard way.

As in other animals such as a cat, if it is tri colored, is it a female only or can males be tri colored in Koi? - Rick

A Koi's colors do not determine its sex. Both male and female Koi can have the same colors.

Tuesday, May 8, 2007

What is a Sakura Ogon? -M Whitebrook

A Sakura Ogon, more commonly known as a Hariwake, is the metallic version of a Kohaku. If you are going to purchase a Hariwake, look for one with a nice Kohaku pattern and a nice metallic sheen.

Saturday, May 5, 2007

Do Koi Hide?

I recently purchased 3 koi and put them in my man made pond. I am unable to locate them. Do koi hide and stay out of sight? I do have a lot of rocks/barriers in the pond. -Mary

When Koi are introduced into a new environment, they are skittish and will hide for a while until they know that it is safe. They are probably hiding in your rocks, you'll be surprised to see how small of a space a Koi can fit into.

If you don't find your Koi for a long time, then something probably has happened to them, either getting sucked into a pump, a bad parasitic infestation, ulcers, or a predator.

Try putting some Koi food into your pond at dawn or dusk to see if they will come out to eat.