Cleaning S/S water tanks

[sailcrazy]

Our boat has 4 s/s water tanks, 3 of which have a single access port. All have internal baffles. When I put a new "whole-house filter" (5 micron,woven) it turns an orangish color within 2-3 weeks. The fill water is via a watermaker, and tests at 260-2760ppm TDS going in, and about the same via a tap. the water tastes OK, and no one has gotten sick so I'm guessing the water quality is OK....except the filter keeps getting all orangish colored. I assume the tanks need cleaning, but am at a loss on how best to do that. Looking for ideas and suggestions on how best to clean my s/s water tanks.

[SailRedemption]

Originally Posted by sailcrazy

Our boat has 4 s/s water tanks, 3 of which have a single access port. All have internal baffles. When I put a new "whole-house filter" (5 micron,woven) it turns an orangish color within 2-3 weeks. The fill water is via a watermaker, and tests at 260-2760ppm TDS going in, and about the same via a tap. the water tastes OK, and no one has gotten sick so I'm guessing the water quality is OK....except the filter keeps getting all orangish colored. I assume the tanks need cleaning, but am at a loss on how best to do that. Looking for ideas and suggestions on how best to clean my s/s water tanks.

You may want to look into having two filters. We just got 2 under sink pentek filter housings for 10 bucks each. Have one sediment filter like your 5 micron to remove the big stuff and a carbon filter to remove the rest, most probably the color as well.. I the two filters ran me maybe $15 for the two of them? Fairly cheap..

I'm in the same boat as you, 3 big ss tanks with baffling and one access Port. I'm going to be shocking my system this month as per practical Sailor suggested

See more @ redemptiverepair.com

[dlymn]

Shock treatment is the way to go to get rid of organic matter. We start the year doing this. Then we add a minute quantity of chlorine (pool chlorine is OK) and use parts per million test strips to keep the concentration right (4ppm).
This is the same process that is used for domestic drinking water. You should use test strips because some supplies might have adequate chlorine and some might not.

Another source of colour might be a poor interior weld which is corroding. Some welds can undergo an alloy separation process and you can be left with ferric material inside. a tiny flaw might discolour the water. A charcoal filter should remedy this

[sailcrazy]

Thanks for the input. What procedure do you use to shock the system? Do you use Clorox or other household bleach, or pool chlorine? How much, and how long do you leave it in the system before wasting it? how many fills and dumps do you do to rinse the chlorine shock out? Have you ever found a way to "scrub" the tank interior beyond where you can reach from the single access opening (ie, behind the baffles)?

[Redline452]

I have a single 400 litre (~100 gallon) stainless tank, also with a single top access and internal baffles. The baffles have a square opening near the top and slots at the bottom, but still pretty much block access. Chlorine etc killed stuff but left the residue.

My first attempt at cleaning involved getting my arm in as far as I could and flailing a cloth around... which I promptly dropped... on the far side of a baffle. I was able to find it with my flex shaft inspection camera, and retrieve it using a flexible spring-shaft gripper, the one where a button on the top extends four claw fingers at the bottom - which gave me an idea. Once recovered, I firmly grabbed a corner of the cloth with the claw, then reached into the tank with the flex shaft and, well, flailed like made over, around, and through the baffles.

With the bit of residual water in the tank (rinsed several times) the cloth did a pretty good job of removing all the scum I could see, even peering around the corners with the inspection camera.

[GBonjour]

Just a thought for you. Food grade hydrogen peroxide is a better way to go. It will kill all the little bugs / bacteria and is better for you than bleach.

[reed1v]

Once you are through with the chlorine and rinsed well, add ammonia to get rid of any oily residue. Chlorine will not do that. Ammonia will. Do NOT mix the two. As a side note, we use to add a bit of iodine to our tanks to kill any bugs that might do us in.

[Dougtiff]

When I bought my latest boat, the faucets didn't have much pressure, so I figured the pressure pump was the problem, installed a new one , no improvement, so I opened up the inspection plate on the tank and discovered there was a fine layer of MUD on the bottom, about 1/8", comes from the city water a plumber told me, after cleaning out the tanks, I installed a filter on the city water hose BEFORE it hits the tanks, no more problem. P.S. had to also clean out the hot water tank, big problem.

[wrwakefield]

Originally Posted by sailcrazy

Our boat has 4 s/s water tanks, 3 of which have a single access port. All have internal baffles. When I put a new "whole-house filter" (5 micron,woven) it turns an orangish color within 2-3 weeks. The fill water is via a watermaker, and tests at 260-2760ppm TDS going in, and about the same via a tap. the water tastes OK, and no one has gotten sick so I'm guessing the water quality is OK....except the filter keeps getting all orangish colored. I assume the tanks need cleaning, but am at a loss on how best to do that. Looking for ideas and suggestions on how best to clean my s/s water tanks.

Hi Sailcrazy,

First, a point of clarification: I believe you may have typoed your watermaker ppm test results? Did you mean 260-270ppm? [not 2760ppm...]

If so, have you tested the water from the tanks? [i.e., without any filters...] If not, consider doing so after sailing around to mix it up. That will help you determine what you may be dealing with...

I agree with the cascading filter approach: We use 3: 1 particulate [which you already have] 1 charcoal [for improved taste and chlorine removal, if any] and- to prevent illnesses when cruising- 1 special potable water filter [at least 1/2µ and/or UV] with its own tap. [For comparison, most of our water is from the water maker also, and is typically just under 100ppm from the water maker; 100-150 from the tanks.]

Regarding cleaning SS tanks, I had them on my last 3 boats and have had good success inspecting and removing what I could through the existing access ports, adding more ports to inaccessible baffled portions where I could, and then using food grade hydrogen peroxide for the final step to purify/sanitize through oxidation what remained. [Cheap and no rinse needed with peroxide... Cleans your plumbing lines as well. After all, sanitized crud is better than the alternative...]

Remember to test PPM from the tanks after you are all finished so you can track your results and monitor the condition of water in the tanks in the future.

If you want to really scare yourself, get a waterproof endoscope/borescope camera with a built-in light [a cheap and handy tool to have onboard...] and inspect your tanks that way...

In case this is helpful.

Cheers!

Bill

PS: Don't forget to filter the water on the way into your tanks, and use your own potable water grade hoses when filling from public sources...

[Brewgyver]

Breweries (and many other industries) clean stainless tanks of all kinds and sizes using a Clean In Place (CIP) regimen, typically using caustic soda, which is rather hazardous. But Five Star Chemical developed a product called PBW to do the same thing quite safely. Homebrewers like myself use PBW to routinely clean beer kegs, SS fermenters, etc.


Fill the tank with hot PBW solution, let it sit for a couple of hours, drain and triple rinse. In this instance, you would want to refill and dump three times. I have personally cleaned salvaged half barrel (15.5 gallon) beer kegs that had been left for long periods with the dregs sitting there hardening, and after the CIP were bright clean.

Five Star also makes a couple of food grade no-sinse sanitizers, but using them in a fixed tank (that you can't shake or roll around to distribute a smaller volume of sanitizer) would definitely be a lot more expensive than chlorine.

[SailRedemption]

Originally Posted by wrwakefield

Hi Sailcrazy,

First, a point of clarification: I believe you may have typoed your watermaker ppm test results? Did you mean 260-270ppm? [not 2760ppm...]

If so, have you tested the water from the tanks? [i.e., without any filters...] If not, consider doing so after sailing around to mix it up. That will help you determine what you may be dealing with...

I agree with the cascading filter approach: We use 3: 1 particulate [which you already have] 1 charcoal [for improved taste and chlorine removal, if any] and- to prevent illnesses when cruising- 1 special potable water filter [at least 1/2µ and/or UV] with its own tap. [For comparison, most of our water is from the water maker also, and is typically just under 100ppm from the water maker; 100-150 from the tanks.]

Regarding cleaning SS tanks, I had them on my last 3 boats and have had good success inspecting and removing what I could through the existing access ports, adding more ports to inaccessible baffled portions where I could, and then using food grade hydrogen peroxide for the final step to purify/sanitize through oxidation what remained. [Cheap and no rinse needed with peroxide... Cleans your plumbing lines as well. After all, sanitized crud is better than the alternative...]

Remember to test PPM from the tanks after you are all finished so you can track your results and monitor the condition of water in the tanks in the future.

If you want to really scare yourself, get a waterproof endoscope/borescope camera with a built-in light [a cheap and handy tool to have onboard...] and inspect your tanks that way...

In case this is helpful.

Cheers!

Bill

PS: Don't forget to filter the water on the way into your tanks, and use your own potable water grade hoses when filling from public sources...

I thought about a 3rd filter as well.. We have similar setups. I use a Sureflo mesh screen filter attached to a under sink filter with a 10 micron sediment filter. This both have standard hose fittings on them for pre filtering water to the tanks. My pressure system only gets filtered with another Sureflo mesh filter to keep crud that may be in the tanks already to protect the pump. I have a separate foot pump that pushes water through the two 10" housings with a Pentek ECP1-10 10" Sediment Filter then to the Pentek FloPlus-10 Filter - 10" Carbon Block Filter to a separate spigot. I figured the tank water is good for showers and sinks but the foot pump will provide us with good drinking water.

I need to one day cut more access ports to my tanks but that is a pain in the but so it's getting put off till we cruising. I'm hoping the dried out drained tanks will allow that brown slime to weaken and fall off during the shock treatment. I'll try to do it when I know the lake will be windy and rough and go motor in side seas to help with agitation.

See more @ redemptiverepair.com

[Terra Nova]

Install a sufficient number of clean-outs in your tanks so you can manually clean them.
Seabuilt - Access Plate Systems

[dlymn]

Most chlorine based sanitisers are derived from the same or similar chemical base and vary because of their dilution rate. I put 1/2 cup of granulated pool chlorine in300 litres, fill with water, let it sit for a hour pump and flush until minimal chlorine taste test using test strips and start using
I have a 5 micron filter on the inlet (I don't use the deck inlet, but connect the hose direct to the filter setup in the sail locker) then a 5 micron and also a charcoal filter after the pump. I also discovered algae build up on the hoses to the taps and painted them to make them opaque.

[Lepke]

No matter your initial water, natural occurring organisms enter the tanks thru the air vents as you draw water out. The orange is some organism. I've seen it several times in fresh water systems that don't constantly add chlorine or something similar. It probably won't hurt you or your toilet would be worn out.
It comes down to do you want to drink a small amount of chlorine all the time? I make all my own water where ever I am. So my tanks are always in use. I chlorinate about once a year unless I see a problem. I think it's better to drink water that has a small amount of organisms that my body can handle than drink chlorine daily.
When I do my tanks I use a rate at the bottom of pool scales. I add the chlorine and then fill the tanks so the water goes up into the fills and vents and leave for an hour or so. Temperature and ph determine time needed to sanitize. I run the water into my lines and let that sit, too. Then dump it all.

[Symphony]

how many people brew their own beer on board?
suddenly makes sense to me....