Adding Access Port To A Fiberglass Tank

Mornin' y'all...

Bess and I are big believers in keeping tanks clean. In our last boat, withing the first few weeks of owning it, we opened the fresh water tank to find some of the most putrid and disgusting water... and we were drinking that stuff!!! So FFW to today. Our new boat has heavy-duty centerline fiberglass tank (100-ish gallons) with no access panel that I can see. So I want to add one. Any tips? Would a standard screw-out port work?



I will try and post pics of the area later today.

Thanks!

Water, fuel, waste ?

Tom:

Sea Built Seabuilt - Access Plate Systems offers off the shelf inspection ports in aluminum and stainless steel, I'd choose the latter for a water tank. They are relatively easy to install, however, where FRP tanks are concerned, if the sealing surface where the port is to be installed is too rough or uneven, it may require some profiling with thickened epoxy, making a leveling shim of sorts. I've done this many times, it's not difficult for someone with composites experience.

Greetings,
Mr. TB. Depending on the baffle arrangement, if any, more than one port may be necessary AND placement of aforementioned baffles should be considered for the cutting of access holes.
Oh, as an aside with your morning coffee...There's a good chance the water you're NOW drinking used to be dinosaur pee.

kulas44 said:

Water, fuel, waste ?

Click to expand...

This is our fresh water tank.

Contact the manufacturer for baffle layout, if any.

That said, I have never felt the need to go into the water tank. I would consider throwing a half teaspoon of bleach per gallon in and going for a ride in some chop then draining. On subsequent fills add 1/8 teaspoons bleach per gallon.

However, for drinking, coffee etc I always use bottled water.

RT Firefly said:

Greetings,
Mr. TB. Depending on the baffle arrangement, if any, more than one port may be necessary AND placement of aforementioned baffles should be considered for the cutting of access holes.

Click to expand...

Yea... I thought of that too. I think I can pull the filler tube and see enough in there to make that call.

Tom.B said:

Yea... I thought of that too. I think I can pull the filler tube and see enough in there to make that call.

Click to expand...

Everyone needs one of these: (or better)

http://www.amazon.com/Solar-Eclipse-SE001CAM-Inspection-Monitor/dp/B003629WRQ/ref=zg_bs_401578011_5

oscar said:

Contact the manufacturer for baffle layout, if any.

That said, I have never felt the need to go into the water tank. I would consider throwing a half teaspoon of bleach per gallon in and going for a ride in some chop then draining. On subsequent fills add 1/8 teaspoons bleach per gallon.

However, for drinking, coffee etc I always use bottled water.

Click to expand...

Navigator went out of business in 2013. However, if you saw what we saw in 2009 when we opened our water tank on our old boat, you would understand why we feel the need to take a peek. I mean, you don't know what people have been putting in there. RV anti-freeze? That sh|t is nasty! Even just general dirt we'd like to get out if it is in there.

Tom.B said:

This is our fresh water tank.

Click to expand...

You can buy something like in your original post for $10 or so or you can spend a lot more and get something that's made for a tank access port.

The one in the photo will be fine if it's mounted on the top of the tank. If you want to put it on the side where it will be covered with water, the more expensive port would be a better choice.

I installed one of the cheap ones on the top of my holding tank. It works.

WesK said:

You can buy something like in your original post for $10 or so or you can spend a lot more and get something that's made for a tank access port.

The one in the photo will be fine if it's mounted on the top of the tank. If you want to put it on the side where it will be covered with water, the more expensive port would be a better choice.

I installed one of the cheap ones on the top of my holding tank. It works.

Click to expand...

It will, indeed, be on the top of the tank.

That type of port should be fine in the top of a water tank. Some fiberglass cuttings are going to get into the tank when you cut the opening. You probably filter the water coming out of the tank so that shouldn't be much of a problem.

HopCar said:

That type of port should be fine in the top of a water tank. Some fiberglass cuttings are going to get into the tank when you cut the opening. You probably filter the water coming out of the tank so that shouldn't be much of a problem.

Click to expand...

Actually, the boat doesn't have one... BUT... adding a filter system to the boat FW system IS on the list.

Tom.B said:

Navigator went out of business in 2013. However, if you saw what we saw in 2009 when we opened our water tank on our old boat, you would understand why we feel the need to take a peek. I mean, you don't know what people have been putting in there. RV anti-freeze? That sh|t is nasty! Even just general dirt we'd like to get out if it is in there.

Click to expand...

Actually Tom it isn't just in boats. I was a contractor for many years and when we would do demo work for a remodel some times I would show people what the inside of their water pipes looked like. It is pretty gross. And it is in everyone's pipes. It is just the nature of water to have things grow in it. If your house is 10 years old you do not want to see the inside of your pipes especially copper pipes.

READY2GO said:

Actually Tom it isn't just in boats. I was a contractor for many years and when we would do demo work for a remodel some times I would show people what the inside of their water pipes looked like. It is pretty gross. And it is in everyone's pipes. It is just the nature of water to have things grow in it. If your house is 10 years old you do not want to see the inside of your pipes especially copper pipes.

Click to expand...

Ewwwww.... Thanks for that.

A couple of months ago, Practical Sailor magazine did a three part series on water systems. The first article was on treating and filtering the water as you put it in the tank. The second article was about cleaning the water system. The third was on treating and filtering the water as it comes out of the tank. It was very well done. A fellow who posts on the Cruisers Forum named Thinwater did the testing. He liked a product called Puriclean, that I bring in from the UK, for cleaning biofilm out of tanks and hoses.

I would be hesitant to use a plastic access panel on centerline tank presumably located below the water line. A hole in the hull into the tank could pop the access panel and sink the boat. I would not be concerned about using that access panel on a tank located above the waterline.

Greetings,
Mr. TB. Mr. T raises an excellent point about sinking potential. I do agree with you that an access port is of high importance for any tank and having seen the quality of your work in person, I'm confident that ANY alterations you do will be of the highest quality so maybe a more robust port is in order.
Our inspection ports (water & fuel on all 4 tanks) are about 2' in diameter and secured with 20 or so 5/8" nuts on studs. I have had the water tank cover off and the tank is cavernous with multiple baffles. From what I could see, there was a very, very slight coating of ??? in a few areas but nothing that gave me any concern.

Yes, the hull integrity point is very valid.

Don't know how handy you are with glass, but the setup Mr. RTF describes would take a little plywood, resin/hardener, saw dust and some good stainless steel hardware. Doesn't have to be perfect finish, it's out of sight.

This would allow you to make a bigger hole, which would be more functional.

Get out the jigsaw!

Greetings,
Forgot to mention...Our access ports appear to be 3/8" thick FRP sheet. VERY robust.

Tomas said:

I would be hesitant to use a plastic access panel on centerline tank presumably located below the water line. A hole in the hull into the tank could pop the access panel and sink the boat. I would not be concerned about using that access panel on a tank located above the waterline.

Click to expand...

I'm a little confused by that statement. Wouldn't a hole in the hull anywhere but in the tank also sink the boat? Please explain how a port in the water tank increases the risk of a sinking.

Greetings,
Mr. WK. You are absolutely correct if the tank is stand alone. I answered with relation to our tanks which are integral to the hull and WOULD pose a problem if holed and not ported robustly enough. Doh! Apologies to those concerned.

oscar said:

Everyone needs one of these: (or better)

http://www.amazon.com/Solar-Eclipse-SE001CAM-Inspection-Monitor/dp/B003629WRQ/ref=zg_bs_401578011_5

Click to expand...

I find this one pretty slick. $20, USB, lottsa cable:

http://www.amazon.com/dp/B00EQNCMTY/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=13TWHCQII2HFB&coliid=IXJQFJ8B4N5TC

WesK said:

I'm a little confused by that statement. Wouldn't a hole in the hull anywhere but in the tank also sink the boat? Please explain how a port in the water tank increases the risk of a sinking.

Click to expand...

I agree, a hole in the bottom of the boat is a hole in the bottom of the boat. A plastic access cover on the tank would not matter.

RT Firefly said:

Greetings,
Mr. WK. You are absolutely correct if the tank is stand alone. I answered with relation to our tanks which are integral to the hull and WOULD pose a problem if holed and not ported robustly enough. Doh! Apologies to those concerned.

Click to expand...

This isn't an issue. The tank is not a part of the hull. It hangs between the two main stringers and does not go all the way to the hull. There is a gap.

Here is a picture. It is a long, narrow, and shallow tank. At the bottom are the overflow tube and gauge connection. At the top are the fill tube and supply line to the pump. I was just thinking I would put it right there in the middle. However, I think I will put off this project until I can add a filter system. Moreover, I peeked into the filler hose connection and the water looked fine-ish. So there really isn't a rush anymore. There are more pressing issues.

In my experience, once you get your tank(s) and water lines clean, they will stay clean and the water will stay safe by making sure you only introduce clean water into the system with a clean, drinking water rated hose that's used for no other purpose and is not left lying around for others to use to wash their boats or rinse their holding tanks.


The procedure for "shocking" the water system has been posted before so I won't repeat it.


City water has been chlorinated and should be safe. If you're filling your tanks with well water, add a little unscented chlorine bleach to the tanks along with the water. A tablespoon or so should do.

If the tank is thick enough you could make your own access cover. A square (or round) 1/4 inch thick piece of 5086 aluminum cut to size and drilled around its outside, about every 1 & 1/2 inches for the cover, 3/8 inch holes. Lay the cover on the tank and mark all the holes and the outside edge. Cut the hole in the tank 1 inch smaller than the cover outline. Drill the holes in the tank to fit 5/16 stainless T-nuts. Insert T-nuts from the inside of tank, pulling them into the (tight) hole you drilled with a bolt and flat washer. Cut a rubber gasket for the lid and bolt it all together. Way cheaper than the sea built units and plenty good for a water tank. FWIW, I was building inspection hatches just like the Sea Built units years before they were.

READY2GO said:

Actually Tom it isn't just in boats. I was a contractor for many years and when we would do demo work for a remodel some times I would show people what the inside of their water pipes looked like. It is pretty gross. And it is in everyone's pipes. It is just the nature of water to have things grow in it. If your house is 10 years old you do not want to see the inside of your pipes especially copper pipes.

Click to expand...

Question please: It is my understanding that water in black plastic jugs does not turn green and grow. Red, blue and yellow ones (like for fuel) all will allow algae growth.

So I'm wondering about replacing my hoses and then covering them with that black foam stuff used to cover hot water hose runs to keep the water toasty. Would that help?

I do have a whole house filter inline after the tank and before the water pump. The hoses "look" okay (clear with red and blue threads) but I wondered if there was anything you'd advise. I don't see anything in the hoses. They are nearly 8 years old and were one of the first things I replaced (after the anchor) when I bought Seaweed.

Thanks.

janice142 said:

Question please: It is my understanding that water in black plastic jugs does not turn green and grow. Red, blue and yellow ones (like for fuel) all will allow algae growth.

So I'm wondering about replacing my hoses and then covering them with that black foam stuff used to cover hot water hose runs to keep the water toasty. Would that help?

I do have a whole house filter inline after the tank and before the water pump. The hoses "look" okay (clear with red and blue threads) but I wondered if there was anything you'd advise. I don't see anything in the hoses. They are nearly 8 years old and were one of the first things I replaced (after the anchor) when I bought Seaweed.

Thanks.

Click to expand...

Hi Janice,
I don't think the color of the hose will make any difference. I do know that plastic or rubber seems to stay cleaner longer than copper or steel. I re plumbed or boat with PEX. We use a charcoal filter at the sink for drinking water.

janice142 said:

Question please: It is my understanding that water in black plastic jugs does not turn green and grow. Red, blue and yellow ones (like for fuel) all will allow algae growth.

So I'm wondering about replacing my hoses and then covering them with that black foam stuff used to cover hot water hose runs to keep the water toasty. Would that help?

I do have a whole house filter inline after the tank and before the water pump. The hoses "look" okay (clear with red and blue threads) but I wondered if there was anything you'd advise. I don't see anything in the hoses. They are nearly 8 years old and were one of the first things I replaced (after the anchor) when I bought Seaweed.

Thanks.

Click to expand...

I'm assuming your hoses are installed in dark places so covering them shouldn't be necessary. I also question why you think you need to replace eight year old water hoses. Water lines in buildings are not replaced on a routine basis, only when they leak (steel pipe will corrode after fifty years or so) and lead pipe is replaced for health reasons.

If you do decide to replace the water hoses, use PEX and be done with it. They will outlast the boat.