Water in water tank

So,

I have no running water in my basement/darkroom, so I use 2x30 liters water tanks. Once when they are filled with water - how long can the water be there before it is stinky, or let's say not good for darkroom use? Maybe to add some additives in the water - to last longer?

Right now I am filling the tanks day before I will make prints, but often some water stays inside.

Anybody had already some experience with this situation?
Thanks.

I too have no running water in my darkroom although the bathroom is across the passage. I get by with bringing enough water for my use during the session, plus a 3 gallon bucket full of water so that I can dunk freshly developed prints before their final wash. It works well for me and has done for over a quarter of a century! The final wash is done in the utility room downstairs

I would say, it depends on your water. If it has some bacteria, and is room temperature, things can grow quickly. If it sits for several days and still seems fresh, you're probably OK. If it starts growing stuff in a week, I would say use fresh water every time.

Hi, I think it's going to be really hard to say. One important thing is the situation before you initially fill the tanks - if they have been wet, and have possibly had some moderate amount of bio-organism growth going on, then it will start much sooner than if the tanks had been thoroughly dry for some period of time.

My experience comes from high volume photofinishing, where we would have problems during our busiest seasons. At those times, we'd sometimes have to run processing systems around the clock - 24 hours a day, and biogrowth would tend to get out of hand in the wash tanks. Other times of year, no problem - the tanks would be drained daily and have time to thoroughly dry before refilling the next day. When biogrowth DID start, I should probably say could be seen by eye, our recourse was to drain tanks, refill and dose with Clorox bleach for perhaps 30 minutes, then drain again and refill for processing. In the industry there was research into biocides that were not detrimental to photoprocessing, but these were pretty expensive.

In the US, the most common water supply treatment is chlorination, but this is gradually lost on exposure to air. So once the water has been in open tanks for a while, the protection is lost. And my personal interpretation, with no solid evidence, is that biogrowth, perhaps from organisms in the air, start growing right away, but take some time to reach an objectionable level (growth is likely at a geometric rate).

I would suggest that at the end of a printing session to add a small amount of "Clorox" bleach to the open water tanks - it will hopefully hold the biogrowth at bay and be gone by the next day. But if there is any trace of fixer (thiosulfate) in the tank, it will neutralize the bleach. If you do a lot of printing, it's probably preferable to completely drain and allow the tanks to thoroughly dry daily. Sorry there's no easy answer.

I have an archival print washer that doesn't have a cover. I have an issue with algae after a few weeks of not using it. It's more of nuisance than anything.

There's a product from Agfa (or former Agfa) which prevents algae and other life forms to grow in water tanks like yours. Agfa Algezid II. It's still manufactured but rather expensive. The other chemical I know of to condition water is calcium hypochlorite (the stuff they put into the cleaning agents).

Andi

What about those sterilizing tablets used in the home brew industry and for cleaning baby bottles and equipment ect.

I have now 10 liters in tank from last weekend, I will inspect the water in couple of days - then I will see does it stinks, anything inside... If yes - I will try some additives, like mentioned above .

darkosaric said:

I have now 10 liters in tank from last weekend, I will inspect the water in couple of days - then I will see does it stinks, anything inside... If yes - I will try some additives, like mentioned above .

Click to expand...

I live in a town with well water. I get filtered surface water for drinking from my mother from the next town over. The containers after a week don't have any issues. Some times for months where I don't scrub out the containers, patches of green algae starts to grow. It doesn't have a odor nor taste. I wouldn't add anything to the water just as a control. If you do run into issues, maybe start thinking about adding disinfectants.

Mr Bill said:

..... add a small amount of "Clorox" bleach to the open water tanks - it will hopefully hold the biogrowth at bay and be gone by the next day. But if there is any trace of fixer (thiosulfate) in the tank, it will neutralize the bleach. If you do a lot of printing, it's probably preferable to completely drain and allow the tanks to thoroughly dry daily. Sorry there's no easy answer.

Click to expand...

Clorox probably contains, in addition to hypochlorite (i.e. "Chlorine") some detergent and perhaps hydroxide to make it fairly strongly alkaline (to make it clean better). This might alter some processes, especially developer. Liquid pool chlorine would be better but is usually sold in large containers which would be inconvenient.

john_s said:

Clorox probably contains, in addition to hypochlorite (i.e. "Chlorine") some detergent and perhaps hydroxide to make it fairly strongly alkaline (to make it clean better). This might alter some processes, especially developer. Liquid pool chlorine would be better but is usually sold in large containers which would be inconvenient.

Click to expand...

That's a good point. Although we did use it in the wash tanks, when there wasn't time to let them dry, we did NOT let any photo material go through this. We drained and refilled the tanks before processing.

Mr Bill said:

... we'd sometimes have to run processing systems around the clock - 24 hours a day, and biogrowth would tend to get out of hand in the wash tanks.

Click to expand...

But the wash tanks make a different situation than what Darko is considering. Wash tanks get brought in gelatin.

Darko though fills his tanks with drinking water fromt the waterworks, maybe even chlorinated (depending where in Hamburg he is located).
The issue of a residu in the tanks can be overcome by spooling that out with a small amount of fresh water.
Another issue might be the house installation.
But the basic of Darko's situation is that his water is nutrient free. Bacteriae that only live in so-called biofilms should not be of interest in this situation.

AgX said:

But the wash tanks make a different situation than what Darko is considering. Wash tanks get brought in gelatin.

Click to expand...

I agree, I had made the unwarranted assumption, on account of the volume, that these would be wash tanks. If it is just for storage, then it should last quite a long time in a sealed container, assuming that it's munipal drinking water. But I have no idea how long.

BTW, a chemist I know, who used to work in a facility with their own ultrapure water system, told me that they would periodically get some sort of biogrowth in their system; it had to be routinely cleaned. So even in the absence of obvious (at least to me) nutrients, some organisms have found a way to live. After hearing this, I've been leery of storing water that wasn't somehow treated.

Harry Stevens said:

What about those sterilizing tablets used in the home brew industry and for cleaning baby bottles and equipment ect.

Click to expand...

Campden tablets are sodium bisulfite not good for mixing developers!

Mr Bill said:

I agree, I had made the unwarranted assumption, on account of the volume, that these would be wash tanks. If it is just for storage, then it should last quite a long time in a sealed container, assuming that it's munipal drinking water. But I have no idea how long.

BTW, a chemist I know, who used to work in a facility with their own ultrapure water system, told me that they would periodically get some sort of biogrowth in their system; it had to be routinely cleaned. So even in the absence of obvious (at least to me) nutrients, some organisms have found a way to live. After hearing this, I've been leery of storing water that wasn't somehow treated.

Click to expand...

Most algae, which is what you are most likely to run into, is green which means it has chlorophyll and makes its own food usually in the presence of light though I have seen times that it looked like it was growing in the dark. I am convinced that treatment plants don't always filter all the algae out and there may always be some to provide a "starter". Most chemicals that will kill algae and other plants might not be good to dip your film in. I think, as has been said before, the answer is change the stored water frequently........Regards!

The stuff I've seen in processor wash tanks is not green algae but slime molds which look a bit like unflavored gelatin. You have a warm environment, approximately 100 deg. F, and a small supply of food, organics from solutions and paper dust and the product is mounds of gel. We cleaned the racks and tanks with Lysol toilet bowl cleaner, Clorox was NOT recommended since it causes changes to the stainless steel. If you chlorinate the tanks you then had to re-passivate the metal. We eventually went to bromide tablets and bromine injectors on our tanks, not sure what the long term results were for the prints but it eliminated the slime. My boss also tried magnets on the water lines (insert big guffaw here).

My stock tanks are filled with city water and kept with a lid on, and 99% of the time in the dark. Those are fine. I do get problems with the open top print washer, and the Jobo, if I don't drain them out periodically. I usually use a citric acid solution and scrub them out if needed (citric acid is one of the components in denture cleaning tablets, which is another option).

darkroommike said:

Clorox was NOT recommended since it causes changes to the stainless steel. If you chlorinate the tanks you then had to re-passivate the metal.

Click to expand...

Stainless Steel is a variety of sorts of steel. Corrosion is not only dependand on type of steel and type and concentration of the likely corrosive element. But also on the duration and temperature, as well as pre-forming and stress of the steel part.
The same sort of steel may be fine for a container but not for a dynamically stressed structural part.
Also the effect of dissolved elements may be considered.

darkroommike said:

... Clorox was NOT recommended since it causes changes to the stainless steel. If you chlorinate the tanks you then had to re-passivate the metal.

Click to expand...

Darkroommike, in practical terms this does not seem to be a problem, provided the concentration of sodium hypochlorite (Clorox active ingredient) is low and you don't leave it for an extended time.

This has long been a standard recommendation in photofinishing to keep bio-growth under control (in wash tanks) when it is not possible to let them dry completely.

I double-checked a reference to this: see Kodak's H-24 processing manual, specifically the second module that can be found here:
http://www.kodak.com/motion/support...ocessing_manuals/h24_modules_online/index.htm

The section is named "Control of Biological Growths." Essentially it suggests to "... add about 2 mL/L of a 5 percent solution of sodium hypochlorite to each [wash] tank as the tank is being filled with fresh water." ... "Use this method intermittently to prevent the buildup of microorganisms." There is a note: "Be certain that the hypochlorite solution is completely removed from the tank before film enters..."

I'd recommend reading the original section rather than relying on my post - I'm pecking this out on a phone and haven't verified it carefully. As a note, this Kodak info is related to motion picture films, and specifically cine processors. These machines are generally more rugged, and the manufacturers specifically make sure they're compatible with standard industry methods. If anyone uses machines that specifically warn AGAINST Clorox, well, the manufacturer probably knows something specific; perhaps they have certain plastics or elastomers that are easily damaged by Clorox.

One last note: as I was involved in large scale processing, we wanted to know just how sensitive stainless steel was to Clorox. So we put a couple samples, 316 and perhaps 304, in covered beakers of a much more concentrated Clorox solution. Both samples DID eventually develop corrosion centers, but as I recall, it took the better part of a week, or perhaps longer. So I don't think the lower concentration for 30 minutes or so would ever be a problem to the standard grades of SS used in photoprocessing equipment.

We only had issues in one tank and I suspect it was a defect in the metal but expensive to repair so we were much more careful after that. The inline bromonators seemed to work much better.

Today I used a darkroom again - and water that was sitting there in a closed tank for a week or so was perfectly clear, and no smell at all.

Pure water cannot breed bacteria ... You need some sort of food for them.

Clorox is a ~5% solution of sodium hypochlorite in water.

Not quite, there is a huge amount settled in films on surfaces inside tubings containing water from waterworks.
As long they stay there they are no danger to us... And if not, they won't form a problem for photographic lab work anyway.

Gerald C Koch said:

Pure water cannot breed bacteria ... You need some sort of food for them.

Clorox is a ~5% solution of sodium hypochlorite in water.

Click to expand...

If you do a search for the MSDS of Clorox you will find other ingredients. Clorox is not sold where I live but the most common laundry chlorine bleach "White King" contains detergent-like components.

darkroommike said:

Campden tablets are sodium bisulfite not good for mixing developers!

Click to expand...

Old thread, but here's a question. What's wrong with using campden tablets for mixing developers?