Fluval Sea Hydrometer provides an accurate and convenient method of measuring specific gravity and salt level in marine aquariums. Regular testing is strongly recommended as stable salinity levels are essential for the health of marine fish and invertebrates. Compact and easy to use, the hydrometer can be permanently installed inside the tank for continuous readings. Its slim, low-profile design camouflages well inside the tank and will not diminish the aesthetics of the aquarium. It can also be used as a portable device, allowing you to take samples simply by submerging it in the water.

The Fluval Marine range of products was launched in October 2012 and includes some great new products, including this range of Fluval Marine Additives, Marine and Reef Salt, a Fluval marine Hydrometer and a number of additional products including LED lighting, circulation pumps and Protein Skimmers. We're pleased to be an authorised dealer that stocks the full range of Fluval Marine products.

Aquacadabra acts as credit broker/intermediary and not as a lender.

Klarna's credit products are provided by Klarna Bank AB, which is authorised and regulated by the Swedish Financial Services Authority, with limited supervision by the Financial Conduct Authority. More information can be found here.

Newpay finance options are provided through Deko’s platform by NewDay. P.D. Aquatics Ltd, t/a Aquacadabra is an Introducer Appointed Representative of Pay4Later Ltd, t/a Deko, which is authorised and regulated by the Financial Conduct Authority (ref no 728646) and is a credit broker, not a lender. NewDay Ltd is authorised and regulated by the Financial Conduct Authority (ref no 690292) and is authorised by the Financial Conduct Authority under the Payment Services Regulations 2017 for the provision of payment services (ref no 555318). More information can be found by clicking the newpay option above, or in the Newpay FAQs.

We really want you to be happy with the product that you've received. If however, when the goods arrive they're not what you want, then no problem - we have a 60 day no quibble return guarantee. Just let us know that you're going to return the item(s) by contacting us(stating your Order Number) and complete the returns packing slip that will have been included with your delivery. This will help us to quickly identify the item that you have returned (unopened and unused) - and we'll put a refund through for you.