Sorry for the English - not sure if you would understand Afrikaans, but if you insist I will translate.

Hypoclear is a solution of metabisulphite and sulphite. The exact composition I can't remember, but I think it is about 10-20 g of each per liter of stock solution. It is published in the Darkroom Cookbook or Film Developing Cookbook. I have never heard of kitchen salt being used to clear fixer. Metabisulphite (usually potassium) is a common food additive, and also used in wine making. It is not expensive at all, and used in many formulas so real handy to have around. Sodium sulphite (natriumsulfiet) on its own will not be sufficient to clear fixer. Kitchen salt (keukenzout) is usually derived from natural resources with many impurities. Sodium chloride is sold as chemically pure, and therefore can be the better choice where NaCl is called for in a formula, but I still don't think it is what you want here.