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Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 6:14 am
by sailor38
Have a 26D and want to keep it in a slip in Ft Pierce, Fl for 6 months. Concerned that sea critters (barnacles, etc) will find the ballast tank a wonderful place to live and grow. Any experience and recommendations about how to handle this? Also, what about possible internal fiberglass blistering problems? Thanks for any help.
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 6:24 am
by dlandersson
Use a pool chlorine tablet in your ballast tank (per the

owners manual) and you'll be fine.
sailor38 wrote:Have a 26D and want to keep it in a slip in Ft Pierce, Fl for 6 months. Concerned that sea critters (barnacles, etc) will find the ballast tank a wonderful place to live and grow. Any experience and recommendations about how to handle this? Also, what about possible internal fiberglass blistering problems? Thanks for any help.
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 6:56 am
by FinallySailing
dlandersson wrote:Use a pool chlorine tablet in your ballast tank (per the

owners manual) and you'll be fine.
Or water sterilizing tablets. That's what I'm using on "Rockhopper". I've read that others use Javax/bleach. It's not only an issue with growth of algae etc inside the ballast tank but if you trailer from place to place there is also the issue of spreading invasive species. Make sure you've barrier coated the bottom of your boat to avoid blistering if you keep her in the water for longer and use antifouling that is recommended for your cruising area (best is ask fellow sailors at your marina what they like to use). I've never heard of an issue with blistering inside the tank - you've got me worried now
BTW: As it is still freezing cold here in England and we've just had fresh snow, I wonder if anybody has tried to simply add salt to the tank. Would also make a great natural antifreeze as well as being to a degree biocidical/biostatic.
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 7:00 am
by dlandersson
Okay, let's think about this...isn't seawater water with "salt" added?
FinallySailing wrote:BTW: As it is still freezing cold here in England and we've just had fresh snow, I wonder if anybody has tried to simply add salt to the tank. Would also make a great natural antifreeze as well as being to a degree biocidical/biostatic.
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 7:20 am
by Obelix
I changed the water several times during the season and added bleach, when I had my

in a slip in SFB last year.
Obelix
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 7:31 am
by FinallySailing
dlandersson wrote:Okay, let's think about this...isn't seawater water with "salt" added?
FinallySailing wrote:BTW: As it is still freezing cold here in England and we've just had fresh snow, I wonder if anybody has tried to simply add salt to the tank. Would also make a great natural antifreeze as well as being to a degree biocidical/biostatic.
Its obviously the concentration of salt that makes the difference between allowing it to be a viable biotope or not and that also defines the thaw point (not sure if that's the right English word).

Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 9:19 am
by Russ
Yup, chlorine tabs work great. Kills everything that lives in the tank. At the end of the season, dumping the tank smells like a swimming pool instead of rotten eggs.
--Russ
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 10:57 am
by Seapup
Concerned that sea critters (barnacles, etc) will find the ballast tank a wonderful place to live and grow. Any experience and recommendations about how to handle this? Also, what about possible internal fiberglass blistering problems? Thanks for any help.
Keep the valve closed and you will be fine. Its dark, sealed and nothing will live in there. Our X stays in a saltwater 9 months a year. No need for chlorine. I would be much more concerned with the bottom and general abuse a boat takes sitting in saltwater for extended periods.
I know adding chlorine is mentioned in the manual as an option, it is just talk to look good on a brochure IMO.

The free chlorine would be used up rapidly and then you just have a tank of plain ol water. You could certainly put it in, but it would have zero disinfectant value after a very short amount of time (unless you want to keep adding more every few days.)
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 12:32 pm
by Russ
Seapup wrote:Keep the valve closed and you will be fine. Its dark, sealed and nothing will live in there. Our X stays in a saltwater 9 months a year. No need for chlorine. I would be much more concerned with the bottom and general abuse a boat takes sitting in saltwater for extended periods.
I know adding chlorine is mentioned in the manual as an option, it is just talk to look good on a brochure IMO.

The free chlorine would be used up rapidly and then you just have a tank of plain ol water. You could certainly put it in, but it would have zero disinfectant value after a very short amount of time (unless you want to keep adding more every few days.)
I can tell you that after a month, the lakewater in my ballast stinks really bad.
The salt in seawater keeps certain junk from growing vs. freshwater. They are even using salt in spas and pools instead of chlorine.
However, seawater also contains living stuff, barnacles, plankton and who knows what else that live just fine in a balanced salt water solution. Without a fresh supply of nutrients, those organisms will die and I would imagine eventually stink. How long will it take depends on the organism. Frankly, I wouldn't want to be near a ramp when a guy dumps 9 month old stagnant seawater that has been bottled up.
I take a small pool chlorine tab and break it up and toss in the vent hole. With the ballast sealed shut, the chlorine will "burn" off organic material, but it has no place to evaporate and stays in the tank until you dump it. After a season, my ballast smells just like a swimming pool. Before using the chlorine, it would knock you out with the rotten egg smell.
As for safety of chlorine and keeping the ballast in, it's fine. No blisters on the inside. No gelcoat in there. Bleach is basically just watered down chlorine, so that works also. I like the idea of the inside of my ballast tank being squeaky clean and organic free.
--Russ
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 1:30 pm
by dlandersson
So, washing your clothes in the ballast tank saves on utility bills?
RussMT wrote:As for safety of chlorine and keeping the ballast in, it's fine. No blisters on the inside. No gelcoat in there. Bleach is basically just watered down chlorine, so that works also. I like the idea of the inside of my ballast tank being squeaky clean and organic free.
--Russ
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 2:40 pm
by Russ
dlandersson wrote:So, washing your clothes in the ballast tank saves on utility bills?
Yep, except the tank seems to eat socks.

Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 3:52 pm
by robbarnes1965
Our local are has lot of , err, "organic" matter in it. The tank can get really funky. I found a little bleach really does the trick too. But it's fresh water.
Would be a good mod to turn the whole tank into a washing machine

Jokes aside, I have tested a cruising trick I read about putting clothes in a sealed 5 gallon bucket with soap and let it swash around all day while you sail. It works great.
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 4:25 pm
by bartmac
Maybe a lump of copper would work....the use of chlorine is possibly an environmental problem?
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 4:46 pm
by mastreb
bartmac wrote:Maybe a lump of copper would work....the use of chlorine is possibly an environmental problem?
As is the use of copper. Free chlorine ions are naturally present in seawater, and they preferentially binds with sodium to form salt in large lakes or the ocean so it's not a significant environmental concern. Biocides like copper and zinc are also normally present in seawater, but they are illegal in some places because they're overly concentrated (San Diego bay, for example).
The most environmentally safe biocide for your tank is salt at high concentrations (>5% by weight), but thats A LOT of salt in your tank. Consider that you're talking about 100lb. bag of salt poured into your tank to get above the salinity required to definitely kill everything in seawater.
A puck of chlorine is much smaller.
Re: Keeping Saltwater Ballast in tank for 6 months
Posted: Tue Mar 12, 2013 5:32 pm
by bartmac
See answers to all sorts of things....great
