best sealant for water tank

[Bob 04 H260]

I have a Hunter 260 with a plastic bow tank. I would like to add a clear port to the top of the tank for inspection / cleaning purposes. I am wondering what would be the safest material to use for caulking ? silicone rubber ?
thanks, Bob

 

[sailingdog]

You need to use a NSF food-grade rated silicone sealant, preferably one that does not acid cure. Here's one example of one...LINK

I have a Hunter 260 with a plastic bow tank. I would like to add a clear port to the top of the tank for inspection / cleaning purposes. I am wondering what would be the safest material to use for caulking ? silicone rubber ?
thanks, Bob

 

[Peggie Hall HeadMistress]

No caulk or sealant is needed...none should be used

Beckson inspection port kits include a rubber gasket that provides a water-tight seal. The threaded cover will have a rubber o-ring. Follow the installation instructions that will be included too.

The sbo.com store carries Beckson ports, but they don't show Beck INSPECTION ports...they show another brand that apparently uses silicone. I'd avoid that one and go with Beckson...they're the best and no more expensive than the cheapest. Dave can order one for you...I'd go with 4".

 

[George H260]

Although I used a silicone caulk designed for aquariums, I have to go along with Peggy. If you use a port that comes with a gasket no caulk should be necessary.

One point. I think 4" may be a little small. With a 6" port I was able to reach into the tank and wipe the sides down. Also, my Little Giant Sump pump fit nicely into the tank with that size.

More at: http://h260.com/water/water.html

My first try I did get some leakage where the screws went thru the plastic but after it cured and I retightend I've had no leaks.

 

[Steve Dion]

I think Bob may be talking about some caulking around the hole that he will need when he makes the cut for the inspection port! These usually have a ring and 6-8 screws that will keep that piece in place.

 

[Peggie Hall HeadMistress]

I think Bob may be talking about some caulking around the hole that he will need when he makes the cut for the inspection port! These usually have a ring and 6-8 screws that will keep that piece in place.

And a gasket under the ring that's all the sealant needed.

I've installed a bunch of these in holding tanks, btw.

 

[sailingdog]

If he already has the inspection port, he may need to use sealant... not all ports come with a gasket.

 

[Bob 04 H260]

good ideas, thanks

lots of great information, I have a clear port, have not opened it yet so I don't know if it has a gasket or not. It has an "O" ring to seal the top.

I looked at the silicone sealant I have and it is FDA approved for the food industry so I can use some of that if required.

I wonder if I could just slide a tight very small "O" ring over the bottom of the port ring so it is inside the bolt hole circle instead of a flat rubber gasket ?

Bob

 

[Peggie Hall HeadMistress]

"I wonder if I could just slide a tight very small "O" ring over the bottom of the port ring so it is inside the bolt hole circle instead of a flat rubber gasket ?"

No. That wouldn't work. The flat gasket is needed to create a seal.

 

[George H260]

We're making this waaaaaaaaaaaaaay to complicated.

You use a zip router to cut the hole in the tank. Then you install the outer ring which is screwed to the tank. You need a gasket or caulk to keep the outer ring from leaking. The port itself has a gasket which is leakproof.

One picture shows the hole cut in the tank. The other shows the port installed.

Click on the picture to expand.