And from Ryuji Suzuki's web site a similar formula (working strength):

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A standard washing aid is:
Washing Aid
sodium sulfite 15g
sodium metabisulfite 5g
water to make 1.0 l
target pH 6.5 to 8

When scum is formed on the solution or processed material, addition of about 0.5g/L of disodium or tetrasodium EDTA with about 1.0g/L of sodium citate is suggested. Stock solution including the EDTA and citrate tends to keep longer.

Kodak Hypo Clearing Agent contains EDTA and sodium citrate to reduce the calcium scum. With hard water, sulfite in the wash aid forms insoluble calcium scum unless EDTA is added. These are also useful in preventing precipitation of aluminium hardener that may be carried over from the fixer (if acid hardening fixer is used).
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