JM350Z

Hi, I have a PH of 8.6 and KH of 230ppm (13 drops in the NT labs test kit).

Is this ok or should I be concerned?

Pond is 2300 gallons being filtered by a cyclone 12 and a 3 tier bakki shower with 100 litres of crystal bio. This has only been running for about a month now but before it was on a fishmate 45000 pressurised filter. The fishmate is still running next to the shower.

Ammonia is 0
Nitrate 20
Nitrite 0.25
Gh 200ppm

Thanks in advance

James

Davej

As long as you don't have much Ammonia and the water doesn't get too warm then its nice and safe with that pH.

It does however make things a little more challenging so the golden rules of not overstocking or over feeding need to be stuck to.

Dave

JM350Z

Ok thanks, I only have 11 medium size koi and I'm not feeding them much at this time of year

JM350Z

I have just tested the water coming out of my carbon filter running at 1 gallon per minute.

The KH is 13dh and GH is 24dh.

Is this right? Why is my tap water so high in alkalinity and shouldn't the carbon filter be removing the particles that make the GH high? Correct me if I'm being stupid!

James

Davej

Hiya

Carbon filter will remove Chlorine, it will not remove Calcium or Magnesium salts that are the main content of GH.

Dave

JM350Z

Right ok, so is this reading too high? Is this normal for tap water? Do I need to change or add something? Thanks Dave

Davej

No it is nice and safe, nothing to worry about.

It is certainly what would be decribed as hard water, my take is that its not ideal for growing and maintaining expensive Koi in, but it will be nice and safe for Koi.

Dave

JM350Z

Thanks so much for the help Dave.

Would you mind advising me how I would go about reducing the GH levels so I can get good growth on the koi next year? Is a water softener an option?

Davej

Reverse osmosis is the best way to remove GH, but it will also remove the KH- this will affect your pH, which would not be a bad thing..

But don't look at GH and pH in isolation, they are only components in an overall package, sticking a v8 in a mini is no good unless you have the brakes and steering to match.

It can all get very boring, most Guys fall asleep half way through.

What filters are you running? what size is the pond and how much stock is in there?

Dave

JM350Z

I'm very interested in this so the more info the better.

2500 gallon pond, a 16000 lph blagdon pump running into a waterco cyclone 12 then into a 3 tier shower filled with 150 litres of crystal bio. I also have a 12000 lph pump running to a fishmate 45000 pressurised filter with 36w uv.

I have 12 medium sized koi

Should I go for a RO system?