Indigo Vat Troubleshooting: Lye and Hydrosulfite

Q: I am using a Philippine indigo paste and the instructions say to melt 100 g of the paste in 10 litres of hot water and then add 1.25g / liter of sodium hydrosulfite and mix until incorporated and then add 1.25g / liter of sodium hydrosulfite and let sit for 20 minutes before dipping.

I followed these instructions but my vat does not seem to be working well. It is very liquidy and weird and a pale blue. Do you have any suggestions for fixing this vat?

A: As an initial matter I would check to see how new your stock of Lye and Hydrosulfite are as they can become less effective if they're aged and oxidized.

I'd guess by your description that your vat was under-reduced (the liquid being blue and dull) which means I'd recommend adding more of the NaOH and Hydrosulfite. I usually add those together into a cup full of simmered water until they are completely dissolved, then incorporate that into the vat, stir the whole thing and check back in half an hour to see where you're at.