Dumb question about Photo-Flo - Duhhhhh

I premix it by putting 1/200 th of a gallon into a jug of distilled, then use it one-shot generally. No worries about contamination, no problems with growing things.
Don't know when I last bought a bottle of the concentrate.

Sometimes I re-use it when I'm getting low and don't have a fresh bottle of distilled on hand.

I want to get one of those hardware store spray bottles (1 litre size) and use it once the neg is hanging as a final rinse.

Will it be safe to store a mixed batch in this bottle or should I make a new, smaller batch each time?

LJH said:

I want to get one of those hardware store spray bottles (1 litre size) and use it once the neg is hanging as a final rinse.

Will it be safe to store a mixed batch in this bottle or should I make a new, smaller batch each time?

Click to expand...

When I did this I would use a bottle pre-mixed with photo flo "stock" solution for at least a month with no problems. I only stopped because my cheap spray bottle stopped misting well. I need to do it again though because it works great. Just got to start from the top of the hanging strip and make sure you spray both sides. If there was a place that sold higher quality spray mist bottles I'd get one as the cheap ones often clog or stop working. When I used it though I would wash the tip in warm water and mist some warm water thru to clear it of photo flo after each use.

pbromaghin said:

I have a dumb question.

I have been tossing my Photo-Flo after every use. Is this a waste? Sure the stuff is cheap, but it can't be all that contaminated after a full rinsing cycle, can it? If you do re-use it, how many rolls is it good for?

Click to expand...

Why bother re-using wetting agent? You're only supposed to use a few drops in the final rinse. Throw it away!

On a side-note, my college used to put a developing tank full of diluted wetting agent for students to dunk their films in after washing them. That's a good idea in theory. One day, while i was developing my film, a noob student discarded his fixer, took out the spiral and dunked it straight into the wetting agent. I chucked the contaminated stuff and made do with 2 drops of liquid soap as an emergency measure. After this, I bought my own 1 litre bottle of Ilfotol, which I'm still using 5 years later!

Cheers,
kevs

rich815 said:

When I did this I would use a bottle pre-mixed with photo flo "stock" solution for at least a month with no problems. I only stopped because my cheap spray bottle stopped misting well. I need to do it again though because it works great. Just got to start from the top of the hanging strip and make sure you spray both sides. If there was a place that sold higher quality spray mist bottles I'd get one as the cheap ones often clog or stop working. When I used it though I would wash the tip in warm water and mist some warm water thru to clear it of photo flo after each use.

Click to expand...

Thanks, Rich.

I've been hanging out the film, then pouring the remaining liquid (in Jobo tanks) over the neg. Real PITA, especially as I need to hold the bottom of the neg to turn it and cup the bottom of the neg to ensure coverage.

As for the bottle, I'm thinking about going to a hairdressing shop (should be interesting with a buzz cut) to get one. I figure that hairdressers need decent quality spray bottles...

Nicholas Lindan said:

I find something does grow in it if you keep it. I imagine enough gelatin washes off the film to feed some sort of cloudy slime.

Click to expand...

I've heard of this but never experienced it myself. I dilute my photoflo into a liter container for convenience and use it as one-session-shot. I keep it up to a month like this. That is, if I process 3 films in one session, I reuse the same photoflo 3 times then dump. Once out of the storage bottle, it never goes back in.

I never had anything grow or have problems. Of course the film that goes into it has been washed for 10 minutes so it's dust free and clean.

Works for me.

I don't reuse my Photo-Flo. I've decanted a small amount into an eyedropper bottle and put only a couple of drops into a tank of final rinse water. Between a bottle I bought new when I started developing film, and another ancient partial bottle given to me by the guy who sold me his used enlarger, I'll likely never have to buy any again!

Terry Christian said:

I don't reuse my Photo-Flo. I've decanted a small amount into an eyedropper bottle and put only a couple of drops into a tank of final rinse water. Between a bottle I bought new when I started developing film, and another ancient partial bottle given to me by the guy who sold me his used enlarger, I'll likely never have to buy any again!

Click to expand...

.
I'm Hoping That You Will Have To Purchase Ten More Bottles, At Least ...

Live Long, And Prosper, And Photograph !

Ron
.

I like Edwal LFN used with filtered water (PUR on sink). Works great.

M.A.Longmore said:

.
Hi Walter,

Where, Is Here ?
{ Hopefully, I have my comma properly placed ... }
I stock up when I can get distilled water for $0.89 Per Gallon.

Ron
.

Click to expand...

Here in Belgium, Europe, I pay 1,00 euro per liter (1.3$/0.3 gallon). I could get it cheaper in 5L canisters, but biking up the hill with two of those...

I have a medicine dropper that I use to measure Photo-Flo 200 and I don't reuse it. I have a bottle that has lasted several years. The darkroom at CPCC does reuse Photo-Flo, but after a week or so it gets a bit dirty and stuff starts to grow (algae? mold? it smells like mildew...).

Me too

patrickjames said:

I like Edwal LFN used with filtered water (PUR on sink). Works great.

Click to expand...

I use a couple of drops of LFN in a pint of water and toss it at the end of my film processing session.

I usually process 3 to 4 rolls of 120mm film in a session and I will mix up a batch of photo flo with distilled water and leave it in a separate tank. After processing and a ten minute final wash I dip the spool into the photo flo and swirl it around for 30 seconds making sure not to create any bubbles. I discard the photo flo after I'm done all four rolls.

Roger Cole said:

Photo Flo will kill them. To make this absolutely photo related, do NOT dump a wetting agent into a stream. Safe down the drain, not to fish. Any kind of soap strips their protective slime coating off and kills fish.

Click to expand...

Photo-Flo is water, propylene glycol, and one of the forms of alcohol according to the MSDS which is on file. Propylene glycol can deplete oxygen from water, thereby suffocating fish.

The chemical definition of 'soap' is 'the alkali salt of a fatty acid'. Photo-Flo has no 'soap'.

Propylene glycol is an approved food additive!

I guess I should have gone to the source at the beginning. Apparently it doesn't matter so much how many rolls you put through it as how long it sits around. As a low-volume hobbyist, I will have to change what I have been doing - mixing up a gallon and using it one-shot until it's gone, which could be several weeks. Now it appears I should mix up only the amount I need for the largest development tank I plan to use and discard it in a few days.

From the Kodak Tech Info Date Sheet TI0688 -

Continuous and Rack-and-Tank Processing Maintenance:

Since the final rinse is not replenished and is further diluted by wash water which may contain bits of gelatin, slime or
algae may build up on the tank surfaces.

Under average conditions, the tank should be cleaned and refilled at least once a week. Conditions of high film
volume or poor water quality may require replacement of the solution daily. Allowing the tanks to stand empty overnight
will help eliminate the formation of algae. For persistent bio-growth problems, the tanks should be cleaned periodically
by treatment with a 5-percent solution of CLOROX or similar chlorine laundry bleach, followed by a thorough rinsing
with clean water.

Storing Solutions:

Concentrates of PHOTO-FLO Solution should last indefinitely if the container is tightly capped.

Because of the convenience and high concentration of the liquid concentrates, mixing of working solution just before
use is recommended. Also because of the high concentration of PHOTO-FLO Solution, "one-shot" use delivers the
highest quality final rinse while remaining economical.

Capacity

The surfactant capacity of a working tank of PHOTO-FLO Solution will depend in part on the amount of film put
through it, the quality of the water used in mixing, and the length of time a working solution is kept in service.
Generally, it is recommended that the solution be changed when it begins to bead, streak, or leave scum on the surface
of films or plates, or once per week, whichever is sooner.

Formation of slime on tank walls, and / or evidence of biological growth in the tank are also indications that the
solution should be changed more frequently.

I don't think anything will grow in PhotoFlo stock.

The problem is using the PF and then returning it to the stock bottle for use next time - as one might do with fixer. Enough organic matter (gelatin ?) and 'essential trace nutrients' get back in the bottle that organic growth seems to appear. The same growth would likely appear in a bottle of distilled water if it was used repeatedly for a final rinse.

Propylene glycol is very benign, and in the concentration used in working-strength PF isn't going to do anything any harm. The active ingredient in PF is Triton X-100 (octylphenoxy polyethoxyethanol - a surefacant detergent, though it can also be called an 'alcohol'), the Triton poses much less risk than what gets flushed down the drain when someone washes their hands.

wiltw said:

Photo-Flo is water, propylene glycol, and one of the forms of alcohol according to the MSDS which is on file. Propylene glycol can deplete oxygen from water, thereby suffocating fish.

The chemical definition of 'soap' is 'the alkali salt of a fatty acid'. Photo-Flo has no 'soap'.

Propylene glycol is an approved food additive!

Click to expand...

Humm, ok. Well that's not the definition of "soap" I intended; yours is much more specific. I didn't even realize the word had a "chemical" definition. By "soap" I mean anything that serves as a wetting agent, reducing the surface tension of water. This would include shampoos, detergents etc. Maybe I should have said any wetting agent would be bad for a fish's protective coating, which I believe to be the case but I could be wrong.

EDIT: After reading the above post by Nocholas I suppose "surfactant" is the more specific word I should have used. I agree it's less harmful than most cleaning products for hands and I certainly wouldn't hesitate to send it down the drain. I wouldn't dump it in an aquarium though, or immerse my hands in one with it on them (or any other household surfactant/detergent etc. either.)

Oh, and how are you guys getting it to last forever? At 1:200, a 16 oz bottle only makes 25 gallons. Are you buying the 1:2100 version? A gallon would still require about 2 ml, which isn't 4-5 drops.

I find the recommended 1:200 dilution wayyyy too much. Two or three drops per film is plenty, if you add more you'll get lots of foam and sometimes even marks on the negatives. That's not the intention, is it?

pbromaghin said:

Oh, and how are you guys getting it to last forever? At 1:200, a 16 oz bottle only makes 25 gallons. Are you buying the 1:2100 version? A gallon would still require about 2 ml, which isn't 4-5 drops.

Click to expand...

Well for one thing, not many people seem to mix it 1:200. I found this FAR too strong, resulting in too much foam and, perhaps paradoxically, weird drying marks. From trial and error I use one drop for every 1.5 ounces of distilled water. I've no idea what ratio that actually is but it seems to last forever.

this also counts for sodium slfite, i think.

I did notice that at 1:200 it takes a lot of rinsing just to get it off my hands. It sounds like a good idea to dilute it more.

When you are getting foam, how much are you agitating? Kodak seems to say that no agitation is necessary at all.

pbromaghin said:

Oh, and how are you guys getting it to last forever? At 1:200, a 16 oz bottle only makes 25 gallons. Are you buying the 1:2100 version? A gallon would still require about 2 ml, which isn't 4-5 drops.

Click to expand...

How much wetting agent do the manufacturers recommend per film/tank? Let's assume I develop 1 x 120 film in a 600ml tank - which would accommodate 2 x 35ml:

First example (1:200): 16 US Fl Oz = 473.2ml. diluted to 25 US Gallons = 94.6L. = 94,600ml. 1 x 120 film in my Paterson tank = 600ml (500ml min). 94,600/600 = 157.6 films per 473.2ml. of wetting agent. 473.2/157.6 = 3.00ml wetting agent per film. That seems excessive to me.

Second example (1:2100 - you didn't say the size of the bottle): 1 US Gallon = 3.78L. = 3,780ml. 1 x 120 film in my Paterson tank = 600ml (500ml min). 3,780/600 = 6.3 films for 2ml of wetting agent. 2/6.3 = 0.3ml per film. That seems about right to me.

My Ilford Ilfotol is in a 1L. bottle that is supposed to be diluted 1:200 = 201L. diluted wetting agent. 201/0.6 (600ml.) = 335 films per 1L wetting agent. 1000/335 = 2.98ml per film. That also seems excessive to me.

These manufacturers' recommended amounts of wetting agent per film seem a little excessive to me - I only use a few drops per tank, so probably the 0.3ml per film recommendation is correct - assuming my maths isn't wrong which wouldn't surprise me! YMMV. Bottom line - if you're getting more than a few bubbles when you agitate the tank you've using too much wetting agent.

Cheers,
kevs

I experimented with this a bit. At 1:200, I get drying marks. At 1:400, I get nice clean negs. At 1:800, I get drying marks.

At 1:400, it's still quite foamy but I agitate gently.

If you use Kodak's recommended amount of Photo-Flo then there is a good chance that you will get greasy spots on your negatives. Four or five drops per 8 ounces is enough. You just want to break the surface tension of the water. This is one of those cases where using twice as much does not yield twice the benefit.