Soft water, hard water

[kiky]

In this crazy hobby of ours, water hardness, among others, is one topic with never ending discussion. There are always those for soft water, at all cost; while others are more cautious.

Those in favour of soft water insist that it is one of the most determining factor to promote tremendous growth rate to attain jumbo-sized koi. In fact in one koi magazine (I forgot what magazine), it was mentioned that in Momotaro, the water is so soft with such low TDS that it almost resembles distilled water! - and look at their growth rate! However, those more cautious always state that too low a TDS makes the water prone to PH crash!

I would like to invite expert opinions on this topic so that we can gain more insight and better understanding, of how soft should our water be for our koi, what are the parameters we should take note of, what is the best system to get the water to the required softness/hardness, etc

[MikeM]

From all I've read, if I had an open system with 50% or more daily fresh water in-flows, I'd want the water to be soft (but not all the way down to distilled) with a neutral pH. The reason is that all wastes produced by the koi are more easily discharged from the body and irritation to the skin is minimized. Calcium etc needed for bone growth etc can be supplied in the food. In a closed system, even with frequent large water changes, there is a need for hardness ... actually KH ... to prevent pH crash, keep nitrifying bacteria healthy and functioning and promote beneficial algae species.

Now, let's hope the guys with all the KH science jump in here.

And then, you also get the question of whether water hardness is needed to get the best finish on certain varieties. Can shiro utsuri and asagi both be brought to prime condition in the same pond?

[dick benbow]

Oh sure mike,
mention my two favorite koi and i can't resist a comment. I was gonna pass
on the expert part...but mention asagi and shiros in the same sentence and ya got me!

most gosanke and shiros do well in similar water. asagi's, hawiwake, midori and the like do better in similar water quite different than gosanke.

as someone who's been keeping koi and noticing things for a long while,
i like to run my water on minimal hardness, with constant water flows to maintain ph. my stocking rate is minimalist as well. I am not a heavy feeder but believe in variety and small amounts frequently.

the only comment i would make about minerals in the water is that it is more CRITICAL for TOSAI and nisai with growing bones and organs and they tend to get thier's more from the water. As adult koi needs are generally met thru food sources.

[jacovors]

I am very lucky to live in an area where my water from tap has a hardness of 80ppm but a KH reading of 30ppm.
To date I never had any problems with my PH and change about 25% water a week.
I believe new water in a closed system to be more important for growth than anything else.
Even my mudpond will be emptied and the clay turned over once a year,
this way keeping the bottom and water fresh.I even do water changes in the mudpond to create the elution of it being much bigger than it really is.
About 40% of the fry in the mudpond have reached 8 inches already and are only three and a half months pld.

[MikeM]

Jaco: When you empty the mud pond to re-condition, read up on treating with lime & whatever are the most current techniques. Brett & Brady may have some mud pond maintenance ideas for you.

[jacovors]

Hi Mike,
When you say read up on this info, where I can I find some to read?.
I will however when the time comes post the question here and hope they respond with some tips.
Thanks for the reply.
Jaco. :wink:
PS Tested the tapwater this morning and it is at 60ppm GH and still 30ppm KH.

[kiky]

My source of fresh water is from a deep well, with a TDS of 200 ppm, which I constantly add to the pond at a daily rate of about 5%. I think the TDS is too high, so I would like to soften this to about 80 ppm.

This morning I have a discussion with a water-softener salesman. He offered me 3 systems:
1. Ion exchange softener, where Ca and Mg are exchanged with Na. I rejected it straight away.
2. Deionizer or demineralizer. This utilises strongly acidic cation exchange and strongly basic anion exchange. It is claimed that it can reduce TDS to below 10 ppm!
3. Reverse osmosis.

Price wise, '1' is the cheapest, while '3' is the most expensive. For running cost, '3' is also the highest. I am most interested in '2' as it is moderately priced with low running cost. But while I am quite familiar with '1' and '3', I am totally unaware with '2'. Is there someone knowledgeable enough who can explain and recommend this system?

[kiky]

My source of fresh water is from a deep well, with a TDS of 200 ppm, which I constantly add to the pond at a daily rate of about 5%. I think the TDS is too high, so I would like to soften this to about 80 ppm.

This morning I have a discussion with a water-softener salesman. He offered me 3 systems:
1. Ion exchange softener, where Ca and Mg are exchanged with Na. I rejected it straight away.
2. Deionizer or demineralizer. This utilises strongly acidic cation exchange and strongly basic anion exchange. It is claimed that it can reduce TDS to below 10 ppm!
3. Reverse osmosis.

Price wise, '1' is the cheapest, while '3' is the most expensive. For running cost, '3' is also the highest. I am most interested in '2' as it is moderately priced with low running cost. But while I am quite familiar with '1' and '3', I am totally unaware with '2'. Is there someone knowledgeable enough who can explain and recommend this system?