Homebrew Perceptol precipitate - cloudyness

[Anon Ymous]

Hello

Five days ago I mixed 500ml of what is rumored to be very close to Ilford's Perceptol. IIRC, it's Edgar Hyman's formula, containing 100g Sodium Sulfite, 30g Sodium Chloride and 5g Metol in 1l of water. The salt used was sea salt, without any additives and I used deionised water (most definitely not steam distilled). There were some particles in the solution after mixing all the ingredients, but a coffee filter took care of that and got a clear solution. I tried it the same day with a roll of APX100 and got some very nice results.

I kept this developer and the next day I noticed that it had gone murky. There seemed to be very fine particles suspended in the developer, which had started to settle a bit, the top 1cm of the developer was almost clear. Now it has almost everything has settled and there's this precipitate at the bottom of the bottle:

So, does anyone have any clue about what might have caused it? Could the salt used be the culprit? Since it's not distilled water, would a water softener (sodium tripolyphosphate) eliminate it? In case I get some chemically pure salt, can I substitute Sodium Chloride with Potassium Chloride, provided that I make a mol for mol substitution (use 27,5% more)?

 

[destroya]

I have made it many times before and it never looked like that. But I always use pickling salt and in a pinch kosher salt. I always use distilled water when making stock developer.

 

[Gerald C Koch]

Sea salt is not pure sodium chloride there is a lot of other crap in it. Stick with the pickling salt. It contains only sodium chloride and nothing else. Any other type of salt may cause cloudiness even kosher salt.

 

[JW PHOTO]

I also use pickling salt with no problems at all and a 5lb. box cost peanuts and lasts for a very, very long time.

 

[Anon Ymous]

Um, uh, what we use here for pickling salt is (refined) coarse grained sea, additive free salt, just like the one I used. All salts here are sea salts. Anyway, in case I use chemically pure salt, can I use KCl as I mention in my original post, if NaCl isn't easily obtainable?

 

[Gerald C Koch]

I really don't know if potassium chloride would work but it should not have any adverse effect. But you should test first. I would correct for the difference in molecular weights.