Tests tap water and freshwater aquariums for general hardness (GH), the measure of dissolved calcium and magnesium ion concentrations, and carbonate hardness (KH), the measure of dissolved carbonate and bicarbonate ion concentrations.
Helps in detecting low KH levels, which can stress the fish by causing rapid pH shifts, and helps owners replicate the natural habitat of their fish.
You can collect items purchased online from Highway Garden & Leisure for FREE. It can take up to 5 days to be delivered to Highway if not in stock at the store (such as in our warehouse), even if it's already in stock at Highway, please wait for your ready-to-collect email before travelling to the store. You will have 7 days to collect your order from when the email arrives.
£5.50 or £10.00 additional charge for orders being delivered to North Scotland, Scottish Highlands & Island delivery zones, please see the below section for more details.
Orders containing one or more items labelled as "Local Delivery" do not qualify for our Standard Delivery and are charged at a different rate (see below, these orders do not qualify for free delivery if over £49.99).
Standard delivery is normally delivered in up to 3 working days, Monday - Friday (Excluding Bank Holidays & Public Holidays) for online orders received before 1pm. Orders received after 1pm may still be processed that day and delivered within 3 working days but in most instances will not be processed until the next working day and then delivered within 3 working days from then. This time frame is a guide and unfortunately not always achievable.
Northern Scotland, Highlands & Isles Delivery Zones
Standard Delivery
Isle of Wight
The following postcodes will incur a £5.50 delivery surcharge:
PO30-PO41
Industrial Scotland, Scottish Grampians, Highlands & Isle of Skye The following postcodes will incur a £10.00 delivery surcharge:
AB35-AB38
AB54-AB56
FK18-FK21
IV1-IV63
KW1-KW14
PA21-PA38
PA80
PH17-PH26
PH30-PH41
PH49-PH50
Heavy Goods Delivery
Isle of Wight & Industrial Scotland
The following postcodes will incur a £7.50 delivery surcharge:
DD1-DD11
DG1-DG14
DG16
EH1-EH55
EH91
EH95
EH99
FK1-FK21
KA1-KA26
KA29
KA30
G1-G84
G90
KY1-KY16
KY99
ML1-ML12
PA1-PA19
PA21-PA36
PA37
PA80
PH1-PH16
TD1-TD15
Scottish Grampians
The following postcodes will incur a £9.00 delivery surcharge:
AB10-AB16
AB21-AB99
North Scotland & Highlands The following postcodes will incur a £22.00 delivery surcharge:
IV1-IV28
IV30-IV36
IV40
IV52-IV54
IV63
KW1-KW3
KW5-KW14
PA33
PA38
PH17-PH26
PH30-PH41
PH49
PH50
Any additional surcharges will be displayed for approval at checkout. In rare circumstances we may be unable to fulfil some orders based on the delivery location and/or the size & weight of the item, if this is the case we will notify you as soon as possible and refund your order.
We reserve the right to amend these selected postcodes at our discretion.
In store purchases
Products purchased in store are not eligible for our standard online delivery services and are not free if £49.99 or over. Availability of, and prices for delivery of in-store purchases will vary depending on the items purchased and store purchased from. Delivery for items purchased in-store is also limited to the local area of the store the item is purchased from and these items are not eligible for delivery to Northern Scotland, Highlands & Isles delivery zones.
A member of staff in store will be able to advise on the availability, price and timescale of delivery for items purchased in-store.
Within the first 14 days of your item being delivered you may decide to return it to us for any reason. If you do we will refund the cost of the item and your initial delivery charge.
Some items are excluded from this policy, and any item returned must be in a resalable condition.
Faulty items
If you discover your product to be faulty within the first 30 days of purchase, please contact us and we will be able to arrange the return of your parcel, for a full refund of your purchase cost, including initial postage price. If you send the product back to us, we will also cover the cost of your return postage to the value of £10.
View the full API range. 
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