fogged fiber paper and potassium bromide

Greetings!
posted this also on LFPF,hopefully someone can help me in either of this sites..

run out of my fresh paper,and reallised that i have some really old fiber paper.i tested them yesterday and nearly all of them showed more or less paper fog,what i could fix with some potassium bromide,some needed more some less,but all could be fixed this way..
tried to print today,made a fresh developer (same amount everything)with the same amount of pot.bromide,the test strips came out good,till the 4th strip..where i could see some fog appear again
it appeared after the 4th small teststrip,no big print..so it didnt got exhausted..
at this time i would like to tell that this is no safelight fog,when i saw the fog, to skip this possibility i just developed and enlarged with the safe lights off..same effect..fog.
added some more potassium bromide,but this made my paper seemingly loose like 2-2.5 grade,on a paper thats contrast is since a long time not as it once was
could someone explain what i am experiencing here,and why?
maybe some same experiences?and how it got fixed?
i really would like to be able to use the papers
the first teststrips showed good useable contrast,and ZERO fog..
any help is apreciated!
my darkroom is a small room on the 7th(top)floor in Barcelona,so it can get pretty warm in there,but it has never been a problem with fresh paper..i use Ansels factorial system,find the emergence time and apply the factor.
im just thinking that maybe the hot temperature caused the pot.bromide to exhaust,or stop to work..after the forth strip(?)
any ideas welcome,please share your thoughts,i would love to fix this paper fog issue,cause as i sad,the first test strip was beautiful..too contrasty,started to tweak the grades made 3 more strips,and i noticed the fog..
i know that there is something,cause i see it,but i dont know why..
i did everything i could(i think)to stop this depressing thing,and it worked for a while,and its still there..my whites look like mud
Please,if you can help me open up my whites for a longer time than 4 test strips!Any idea welcome!
Thanks folks!AlltheBest!
monk

How much Bromide did you add to your developer? There are several effects which can influence bromide level and action in your developer:

1. Development releases bromide, assuming your paper is a Silver Bromide or at least Silver Chlorobromide based paper. Can you tell us your exact paper type?
2. Bromide in solution displaces Chloride from Silver Chloride grains, therefore a Silver Chloride paper will release chloride and reduce bromide level in developer.
3. In low quantities bromide is a restrainer, but at very high concentrations it turns into a mild silver solvent which will actually increase developer activity.

Here is what you could do:

1. Try different restrainers, like Benzotriazole, Phenyl-Mercaptotetrazole, or Potassium Iodide, and check whether these eliminate the fog.
2. accept the fog and carefully bleach it back after fixation and washing.

Be aware that really bad fog cannot be helped since the amount of potassium bromide adverse effects on the paper.

Gerald C Koch said:

Be aware that really bad fog cannot be helped since the amount of potassium bromide adverse effects on the paper.

Click to expand...

It also adversely affects the developer, particularly if it contains Metol.

Ian

Rudeofus said:

How much Bromide did you add to your developer? There are several effects which can influence bromide level and action in your developer:

1. Development releases bromide, assuming your paper is a Silver Bromide or at least Silver Chlorobromide based paper. Can you tell us your exact paper type?
2. Bromide in solution displaces Chloride from Silver Chloride grains, therefore a Silver Chloride paper will release chloride and reduce bromide level in developer.
3. In low quantities bromide is a restrainer, but at very high concentrations it turns into a mild silver solvent which will actually increase developer activity.

Here is what you could do:

1. Try different restrainers, like Benzotriazole, Phenyl-Mercaptotetrazole, or Potassium Iodide, and check whether these eliminate the fog.
2. accept the fog and carefully bleach it back after fixation and washing.

Click to expand...

Hi Rudeofus!thanks for your thoughts!
sorry i forgot to mention,i used 50ml of 10%pot.bromide with 2 liters of 1:9 ilford multigrade some paper did well with the 50ml,some needed 100
the papers i used now are in the 50ml group...and both Ilford Multigrade fiber base,one is the MGF.1K and the other MGFB.5K
the next in mind for me would have been Benzotriazole too,or some other restrainer,and give that a try,actually wanted to start with benzo,but since they had the pot.brom. i went with that...
tried bleaching with ferri,but (as i experienced before too)bleaching is not for me..
i still have to try the bleach that Ansel mentions in his book "The Print" as he says i quote "it has a very little tendency to cause stains"
Thanks!

Gerald C Koch said:

Be aware that really bad fog cannot be helped since the amount of potassium bromide adverse effects on the paper.

Click to expand...

Thanks for your thoughts Gerald!that is the reason i used just the 50ml group(one group needed 50ml other 100 to clear up)to make things "sure"
I was just surpriced,cause it worked out for 4 strips,the margin was paper base white,and than it stopped to work..the possible cause of this im triing to understand here,it worked well,and after a very brief time it fogged again...

Ian Grant said:

It also adversely affects the developer, particularly if it contains Metol.

Ian

Click to expand...

Hello Ian,Thanks for the thoughts! i found now online that there is no Metol in the developer i used(Ilford Multigrade)

This may be a futile effort. I would buy some fresh paper.

The problem with potassium bromide and other restrainers is that eventually you get a very unpleasant soot and chalk effect.

Gerald C Koch said:

The problem with potassium bromide and other restrainers is that eventually you get a very unpleasant soot and chalk effect.

Click to expand...

That depends on the paper, warm tone papers will get significantly warmer.

Ian

just an update Folks..
today tried it again,and it worked like a charm,today the paper had a better mood i guess.
had to give 160ml more from the 10%pot.brom. to the developer,and the exposure changed from 20 sec to 75sec,but it all worked out well
made 2 printsim really glad!!
no idea what could have happened yesterday
measured everything to stock solution..mistery..
Thanks Everyone!
Best!
monk

A common darkroom mistake which causes fogged results is developer contamination with fixer. Any chance that this happened?