# Test kit ZOOLEK TEST GH-KH for measuring general hardness (GH) and carbonate hardness (KH)

**URL:** https://aio.lv/en/product--zoolek-23655--12092156
**Data updated:** 2026-03-13 15:51 (EET)
**Category:** Aquarium Supplies
**Manufacturer:** ZOOLEK
**Manufacturer code:** 23655
**EAN:** 5907527410105
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 11.99 €
**Prices and availability valid until:** 2026-07-12 23:59
**Price without VAT (21%):** 9.91 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--zoolek-23655--12092156

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 06.07.2026 | free |
| Pickup points | 09.07.2026 | 1.99 EUR |
| Courier delivery to door | 09.07.2026 | 4.99 EUR |

## Summary description

ZOOLEK TEST GH-KH is a test kit designed to measure water general hardness (GH) and carbonate hardness (KH). It provides simple, quick chemical testing to assess mineral content relevant for aquariums, ponds and water conditioning. Use it to monitor hardness levels for fish health, plant growth and water treatment adjustments.

## Long description

ZOOLEK TEST GH-KH is a chemical test kit for measuring general hardness (GH) and carbonate hardness (KH) in water. The kit is intended for routine checks of mineral content in aquarium and pond water as well as for monitoring water used in conditioning and treatment tasks. The test kit delivers colorimetric results that help evaluate calcium, magnesium and carbonate/bicarbonate levels affecting fish health, plant growth and buffer capacity.
Advantages
The kit offers a straightforward titration-based procedure with visual color change endpoints for both GH and KH parameters, enabling quick assessment without specialized instruments. Test reagents are formulated to provide clear, distinguishable results over typical freshwater hardness ranges. The compact kit design includes the necessary reagents and an instruction leaflet to perform repeated measurements at home or in small-scale professional settings.
Suitable for
 Freshwater aquariums and planted tanks monitoring
 Pond water quality checks for ornamental fish
 Pre-treatment and post-treatment checks in water conditioning
 Routine hobbyist and small laboratory hardness testing
Key specifications
 Measured parameters: general hardness (GH) and carbonate hardness (KH)
 Measurement method: colorimetric titration with visual endpoint
 Suitable water type: freshwater (aquarium and pond)
 Result format: discrete hardness values expressed in degrees or ppm equivalents (via color change steps)
 Package contents: reagents and instruction leaflet for multiple tests
How to use
Collect a sample of the water to be tested in a clean container or the supplied test vial. For each parameter follow the kit instructions: add the specified number of drops of reagent to the sample and perform titration until the color change endpoint is reached. Compare the color transition or count titration drops as directed to determine the GH and KH values. Rinse glassware and cap after use and store reagents in a cool, dark place according to the printed instructions.
Usage recommendations
Perform tests regularly to track gradual changes in hardness and buffer capacity; test after water changes, when adding new livestock or plants, and when adjusting water chemistry. Use fresh reagents and follow the temperature and sample handling guidelines in the instruction leaflet to ensure repeatable results.

## FAQ

### How much does the ZOOLEK TEST GH-KH test kit cost, and is it available for purchase?

The price is 11.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 8 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 06.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All ZOOLEK products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized ZOOLEK service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

https://aio.lv/img/cache/product/12092156/67608216_large.webp