Potassium Oxalate developer mixing problem

Hi Folks,
I was watching one of Bill Schwabs (rest in peace) videos about mixing potassium oxalate developer and I followed his method and ended up with a lot of white sludge which I’m assuming is oxalic acid that didn’t go into solution.
His recipe was for 1 liter add 200 grams potassium carbonate until dissolved then slowly while stirring add 230 grams of oxalic acid. After all the fizzing was over I have quite a bit of sludge that didn’t go into solution. I’ve done this before with different recipes I believe and didn’t have that problem. Do I just filter out the sludge or do I add more potassium carbonate until dissolved? Or do I start over with a different recipe? Thanks for any help!

I mix my own as well. Personally I would just check the ph and then decant the solution off the sludge and then test it. Actually it happened to me once when I accidentally put in too much OA. I dried the "sludge"and put it in jar in case I find a use for it.

I am interested in others mixing ratios, I purchase PO directly from a source in Quebec, I use 1200 grams to 4 litres, it seems like a pretty potent mix but
it works well for me as a developer, I resuse over and over and I do strain the PO through a screen time to time which takes away some of the sludge.
What are others mixtures for you Pt PD developers?

dpurdy said:

I mix my own as well. Personally I would just check the ph and then decant the solution off the sludge and then test it. Actually it happened to me once when I accidentally put in too much OA. I dried the "sludge"and put it in jar in case I find a use for it.

Click to expand...

Thanks for the info. I just added a bit more potassium carbonate (maybe a tablespoon or so) and it fizzed up again and just a bit of sludge was left which I’m hoping means it’s ok to decant and use. I pulled out the ph meter to check but alas the damn thing won’t calibrate anymore meaning I need a new electrode.

Carnie Bob said:

I am interested in others mixing ratios, I purchase PO directly from a source in Quebec, I use 1200 grams to 4 litres, it seems like a pretty potent mix but
it works well for me as a developer, I resuse over and over and I do strain the PO through a screen time to time which takes away some of the sludge.
What are others mixtures for you Pt PD developers?

Click to expand...

I’m not sure of a correct recipe but most seem to have more potassium carbonate than oxalic acid. In Bills recipe it was the opposite. I’ve never had the sludge problem until I tried Bills recipe. But it seemed to work for him in his video. I’m no chemist so my knowledge is anecdotal.