Bulkhead Koi Tank Connectors for hydroponics aquaponics Koi ponds
The price you see is the price you pay, postage and packing are already included. Items will be despatched First Class Royal Mail post by the end of the next working day at the latest but normally if ordered before 1600 Hrs they will be despatched on that day.
Used in Koi and fish pond filtration systems. Particularly useful in DIY blue barrel filter setups as shown in the uniseal images at the bottom of the page.
DuPont Uniseals® from Seals4U - The price you see is the price you pay, no extra postage (that is included in the price), no import duties,
no import disbursement fees, no extra VAT. We use these ourselves and have invested in the idea of Uniseals® and imported directly from the USA, all
fees and taxes are paid. We operate as a UK business and happily export outside of the UK. To purchase in the UK please use the
UK Uniseal pages where prices are marked in UK Pounds, from the EU
please use the EU Uniseal pages where prices are marked in Euros.
We sell all standard sizes of Uniseal® on this web site and we have replenished our stocks so also sell packs of five and ten Uniseals® at
further discounted prices. We also sell Uniseals® on Ebay.co.uk as Seals4u here.
If you would like to purchase Uniseals® for delivery outside of the UK or the EU
email me for postage costs.
We aim to be the least cost option for fast delivery of all standard Uniseal® sizes up to 4 inches to your door in the UK so if you find DuPont Uniseals®
advertised by any business at a lower UK delivered cost elsewhere then please let us know. We operate a
Lowest Price Guarantee in the UK - Simply -
If you find a Uniseal pack price that is lower from another online business retail store, we will match the price. This of course means that we are still very competitive in the European marketplace.
There are other Uniseals available in different sizes and colors. If you wish to purchase these then get in touch with us here.
DuPont Alcryn Uniseals® - connect pipes to tanks without bulky bulheads, tank connectors, nuts and bolts, "O" rings or messy
silicone to fill the gaps and using only one part.
Uniseal® products replace traditional plumbing hardware with a single injection moulded unit requiring no component parts. They were designed by Dupont to
solve many of the issues of pipe to tank connections. For many industries pipe to tank seals are traditionally among the most complex connections to
manufacture. Traditional seals require multiple parts such as, rigid flanges, bolts, washers, o-rings, along with long assembly times and high
production costs for businesses.
The DuPont developed Alcryn® is the key to the liquid-tight seal. When the pipe is pushed through the rubber-like Uniseal® from the outside,
the inside Alcryn® wall becomes thin enough to allow the pipe to squeeze through and then forms a liquid-tight seal. The coefficient of friction
with the plastic pipe is higher using a Uniseal® than any other material which allows it to create a better liquid tight seal.
Uniseals® will connect pipes to complex contoured surfaces without deforming the tank and are compatible with both water and oil based materials.
Standard Uniseals® are made to fit ABS, PVC and steel pipes from 3/16" (5mm) to 6" (150mm) through tank/vessel wall thickness of 1/8" (3mm) to 1/2" (13mm).
The greatest assets to Uniseal® products are that they have a quicker and easier installation process and pipes can be removed and replaced at a
There is no requirement to cut a pipe exactly to length to fit into a bulkhead, the pipe passes straight through the wall of the tank, whether it is a flat
or curved surface, surrounded by the Uniseal® and no solvent welding is required. There is some leeway on the angle that the pipe passes through the
Uniseal® (up to 15 degrees) so unlike normal bulkheads some building tolerance can be applied.
The effort is worth it, pipes and Uniseals® can be removed and with care re-used time and
again. No more having to cut solvent welded fittings from pipes or having to fit expensive rubber boots due to design changes or mistakes.
Want to change the design of your entry point into your vessel, simply leave the Uniseal® in place, leave a short length of pipe and cap it off.
Uniseals® are also ideal for a hydroponic bucket system as with some care they are re-usable.
Some interesting Uniseal testing. This time by an informed Reef Tank hobbyist.
Koi pond filter systems
Koi quarantine tanks
Air line introduction into tanks
Fish pond filtration
Aquaponics reservoir and water systems
Hydroponics reservoir and water systems
Aquariums with external filters
Reef aquarium systems
Rainwater collection systems
Connecting IBC containers
Connecting blue barrels
Connecting water barrels
Yacht and motorboat chandlery
House filtration systems
Only one tool is required to achieve a watertight seal - a holesaw.
Uniseal® Fitting Instructions
Cut a hole to the correct size using a holesaw. A wee tip here - run your holesaw as slowly as is possible, the bigger the holesaw
the slower you want it revolving. Don't burn out the holesaw or melt your plastic vessel.
Ensure there is no swarf around the hole. A fine sandpaper will remove excess.
Insert the Uniseal® into the hole from the same direction that you intend to insert the pipe.
Ensure that your pipe has a clean cut end. Chamfering the end of the pipe helps when it comes to insertion.
Lubricate the outside of the end of the pipe with soap/washing up liquid and then push the pipe through the wide side of
the Uniseal® and into the tank. On larger pipes silicone lubricant instead of soap applied to the pipe and Uniseal® further helps ease insertion.
The pipe can be moved backwards and forwards to achieve the correct position.
Uniseal® Installation Tips
Some larger diameter pipes may require more force to insert them through a Uniseal®.
Ensure those pipes have a good chamfer on the end to be inserted.
Silicon pipe lubricant spray will also create less friction between the pipe and the Uniseal®.
Rocking the pipe gently from side to side when applying pressure will also aid insertion.
Use a block of wood to push the pipe through the Uniseal®.
Just prior to inserting the Uniseal® heat it by immersing in hot water for a minute.
For particularly stubborn installations use a ratchet strap around the vessel and the end of the pipe you would like to insert. Slowly ratchet the pipe through the Uniseal, tap the free end of the pipe with a dead blow hammer on a piece of wood.
There are a few hints and tips on the following videos which some people use to insert their Uniseals®.
Pipes come in different sizes. The outside diameter of your pipe can be checked out from this website
www.pipestock.com/ who sell different classes (pressure rating) of pipe in different materials.
Don't get overly hung up on your pipe size unless you intend to pressurise your tank or vessel, Uniseals® have a little tolerance of around 2mm
on larger diameter pipes. The main criteria is that your pipe fits tightly through the Uniseal®.
Some Uniseals in situ. This is from a DIY blue barrel filter system on a fish pond.