Links To Koi Industry East_Riding_Different_02.jpg (4104 bytes) East Riding Koi Co.  One of the UK's finest Koi sites. UK.gif (11944 bytes)  



NT Labs Water test Kits

GH (General Hardness) – What is GH?

General Hardness is a measure of the sum total of minerals dissolved in the water. Water can be either ‘soft’ or ‘hard’ depending on the amount of dissolved minerals, (the more minerals the greater the hardness) I am sure we have all had experience with GH – lime scale in your kitchen kettle for example……..

Why do I need to test for GH?

The dissolved minerals that make up the hardness of the water are all essential for the biological processes that occur within the pond. If the hardness is too low then these processes cannot function sufficiently, and the pond will begin to stagnate. Regular testing is essential, as the GH will decrease as these minerals are used up by the pond life.

What are the correct GH levels for my pond?

This test kit measures GH in odh (where one degree = 17.8 PPM CaCO3). Maintenance of a level of at least 8odh will ensure the biological processes f the pond can continue to function. The ideal level lies between 10 and 5odh.

What should I do if the GH level is wrong?

Test the GH of your tap water (or spring water etc). If it is above 8odh then regular water changes should insure that the GH level is topped up. If your tap water is below 8odh then use Koi Care & Minerals Up. This can also be used to boost GH in healthy ponds. If the GH value is low it is vital to check the PH and KH of the water as well.

KH (Total Alkalinity) – What is KH?

KH, is also known as Total Alkalinity or Carbonate Hardness and is a measure of the buffering capacity of the water in your pnd. The buffering capacity refers to how well the pond can resist changes in PH.

Why should we test for KH?

Established ponds tend to acidify over time. This decrease in PH is due to the releae of organic acids by he fish and the release of acidic substances by the beneficial bacteria in the pond and your filtration units. The buffer in the pond counteracts this change by effectively ‘mopping up’ these acids preventing the natural drop in PH. If the pond is allowed to drop in PH your fish will become very unwell…..

Ponds with excessive algae can show large PH fluctuations on a daily basis. This change is prevented if there is a sufficient KH level. This is why it is so important to regularly check and maintain the KH as it will eventually become exhausted……

What is the correct KH level for my pond?

This test kit measures KH in odh (where one degree = 17.8 PPM CaCO3) It is essential to maintain a minimum of 4odh at all times. A KH of between 6 and 8odh is more desirable.

What do I do if my KH level is wrong?

Firstly check the KH level in your tap water (or spring water etc). If the level is above 6odh then regular water changes should keep the KH value in the pond topped up to a reasonable level. If the KH value is below 6odh then perform water changes and boost the KH of your pond using Koi Care KH (Buffer) UP. To maintain a healthy KH level in your pond regular additions of a good quality Clay. If you do have a low KH level it is vital to regularly check the pH of your pond to ensure it has not dropped too low.

SKU Description


NTLAB-NTT-324   NT Labs GH/KH Hardness Test Kit
  (80 Tests)
£6.70 + Vat Order

Where postage charges are not shown on the final order - the appropriate charge will be applied but will be kept to a minimum


A Very handy 'Digital' Thermometer which simply hangs on the side of the tank or pond - it has a probe which then just hangs in the water for an accurate reading. 
SKU Description


THE-425 Digital Thermometer £8.93 + Vat Order


Larger Digital Thermometer - very easy to read and provides temperatures both Inside and Outside - this superb thermometer has a waterproof probe of course that simply hangs into the water of the pond or the tank .. 

SKU Description


THE-427 Digital Thermometer In/Out £14.70 + Vat Order



 Non Chemical Treatments - Parazoryne and Sabbactisun


Please contact us if we can help in any matter <>