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King British Aquarium Sealant 78g

Code: 17940
  • £5.75
Item out of Stock   |   Usually dispatched within 24 hours

King British Aquarium Sealant is ready to use silicon sealant for making & repairing aquariums.

King British Aquarium Sealant is a silicone sealant ideal for aquaria building/repair, mounting valves and sealing connections. It offers a permanently flexible, watertight seal and excellent adhesion even under extreme pressure. It is harmless to fresh and saltwater fish. Available in 25g and 78g pack sizes.How to useAll surfaces to be sealed must be clean, dry and free from grease. Surfaces can be cleaned using methylated spirits, applied to a tissue or cloth, before applying the sealant. Remove cap and pierce tube diaphragm (25g size) / Remove nozzle, cut off the end of plastic cartridge and screw on the nozzle (78g size).Cut tip of the nozzle to the required width of seal. The nozzle opening must always be wider than the joint to be sealed, allowing the sealant to make contact with both surfaces. Press the tip of the nozzle against the sides of the joint and hold the tube/cartridge at a 45-degree angle. Push the tube/cartridge while applying a steady, even pressure at the base. Ensure that a bead of sealant is ahead of the nozzle as it moves forward. Smooth any inconsistencies to the finished bead with a wet instrument such as a spoon or spatula. Smooth surfaces lightly ensuring sealant makes contact with both surfaces whilst still un-cured. Any excess of misapplied sealant should be removed whilst still un-cured using a tissue or cloth soaked in methylated spirits. After completing the application, ensure that the sealant is kept dry and undisturbed for at least 48 hours. N.B.The sealant must be fully cured before the aquarium is filledAvoid contact with skinUse only in well-ventilated areas Health & SafetyWarnings: The sealant must be fully cured before the aquarium is filled. Keep out of the reach of children. Avoid contact with skin. Use only in well-ventilated areas.

What is aquarium sealant?

Aquarium sealant is a type of adhesive that is specifically designed for use in fish tanks and other aquatic environments. It is used to seal joints and seams in the tank, as well as to attach decorations and other items to the tank.

Aquarium sealant is typically made from silicone, which is a waterproof and flexible material that is resistant to deterioration from water, heat, and chemicals. It is specifically formulated to be safe for use in aquatic environments, so it does not release any harmful toxins or pollutants into the water.

To use aquarium sealant, you typically apply a small amount of the sealant to the joint or seam that you want to seal, using a caulking gun or other applicator. You then smooth the sealant with a wet finger or tool to create a smooth, even surface. The sealant will typically take several hours to cure, during which time you should avoid disturbing it or adding water to the tank.

Aquarium sealant is an important tool for maintaining a fish tank and ensuring that it is watertight and safe for the fish and other aquatic life living in the tank. It is important to use aquarium sealant carefully and to follow the manufacturer's instructions to ensure that it is applied properly and safely.

Payment Methods

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Next Day Shipping Upgrade - Cut off Midday (12 pm)

Please Note: We only deliver ponds and pond plants on our own delivery vehicles!

The blue highlighted area on the map below is where we deliver on our own vehicle! Unfortunately, if you are not in one of these postcode zones we are unable to deliver certain items such as plants, small glass items and selective other products.



We offer a few different delivery options depending on the size and value of your order.

Orders over £50 qualify for free mainland UK (excludes Northern Ireland) delivery which will arrive within 3-5 working days of the order being processed.


Residents of Northern Ireland, please provide your EORI or XI Number.

If you do not have one, please follow the information at


Orders Below £50 in Mainland UK will be charged a standard delivery fee of £5.99.

Additional Shipping Charges

For any orders that do not include Aquariums, the below is charged:

Next Working Day Parcel Delivery to Mainland UK - £7.99 OR £2.99 if the order is over £50

Standard Parcel Delivery to Northern Ireland £8.99

Standard Parcel Delivery to Scottish Highlands & Islands £9.99

Standard Parcel Delivery to Jersey & Guernsey £12.99


For all Aquarium deliveries (Excluding biOrbs & Smaller Aquariums), the below is charged:

Next Working Day Pallet Delivery - £20

2 Hour Booking Slot Pallet Delivery - £20

Pallet Delivery to Northern Ireland - £38

Pallet Delivery to Isle of Wight (PO36 and Above) and Scottish Highlands (AB, PH, IV1-36, IV63, KW1-14, KY, PA21-41) - £38

Pallet Delivery to Southern Ireland - £48

Pallet Delivery to Offshore postcodes (KA27-28, PA20, PA42-49, PA60-90, ZE, JE, GY. IM) - £70

Pallet Delivery to the Scottish Isles (IV40-56, KW15-17) - £90

Pallet Delivery to Outer Hebrides (HS) - £120