May Bank Holiday open 10am until 3pm.  

We are open 7 days a week, 9am to 5pm Monday to Friday & 10am until 3pm weekends (Winter Hours and Bank Holidays vary) 

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The NT Labs Nitrite Test Kit provides a simple, easy to use testing kit for determining Nitrite (NO2) levels in both ponds and freshwater aquariums. The NT Labs Nitrite Test Kit comes complete with test tube and liquid reagents to provide accurate results for 40 tests.

Nitrite is produced by the beneficial bacteria in the pond and filters as they break down the harmful waste ammonia excreted by the fish. Nitrite can affect the health of fish but is now as toxic as ammonia.

As well as irritating the surfaces and gills of the fish the main factor leading to nitrite poisoning is the corruption of the structure of haemoglobin, the oxygen carrying agent of blood. Nitrite causes the addition of a methyl group to haemoglobin, forming methhaemoglobin which cannot carry oxygen, thus asphyxiating the fish. This disease, called meth-haemoglobinaemia can be recognised as the fishes blood turns from red to brown.

Check the nitrite concentration of your koi pond using a NT Labs Nitrite Test Kit. The nitrite level of the water should always be zero. (Unless just starting up)

The appearance of any colour in this test indicates a warning that the filter system is not working perfectly.

Water Issue Nitrite

We aim to dispatch orders received before midday Monday to Friday on the same day where possible. In most cases our items are available for 1 to 2 day delivery at a competitive price and are trackable via DPD or APC.

Delivery costs for standard items in the UK - £5.95

(Surcharges do apply to remote postcodes)

Heavy items - £9.95

Pipe - £14.95

Palletised items - Some large oversize products, typically items weighing more than 30kg, may require delivery via pallet. Standard Pallet charge is approx. £50.00. To ensure there are no delays with delivery, please include a contact number when placing the order.

Overseas – DHL and UPS, cost based on weight / volume at checkout.