- These are answers to questions that frequently come up in conversation with avid bubbleheads.
How do you adjust a recipe's dilution?[]
See next question.
Do you adjust water, detergent, polymer, or what?[]
It depends. The relationship between the ingredients in a mix is complex. The amount of polymer needed, for example, is not strictly a function of either water amount or detergent amount or total juice amount -- though in some dilution ranges, you can treat it that way.
Generally, I think of the amount of polymer as most strongly tied to the amount of water in the juice as long as I am making adjustments in a similar dilution range. If think I may need to add a lot of water in the field, I will bring some extra polymer (usually in a solution such as BLM or a 1% guar or HEC or PEO solution) and some baking powder (since baking powder is forgiving and does not require careful measuring -- whereas citric acid needs very careful measurement to avoid overdosing the juice). I will add the water that I think I need and an appropriate amount of baking powder and see how things work. If they work well, I leave it alone. I will add a bit of polymer solution if the mix became less friendly.
If I anticipate needing to adjust dilution in the field, I make the bubble juice at the most dilute that I expect to use and add detergent (and baking powder or 5% citric acid solution) little-by-little till I get the film that I want.
It is generally easier to add detergent in the field (as long as you don't overdo it) than water -- since adding a lot of water also generally necessitates adding polymer, too.
If I am playing with dilutions for a recipe that I don't plan to change in the field, I adjust the amount of detergent and keep everything else the same.
As a note: when solutions are quite dilute, they often need a bit more polymer per amount of water than solutions with more detergent. I would say roughly that if you adjust a recipe intended for 16:1 (water:detergent) or less then you should increase the amount of polymer. Somewhere around 30 or 35:1, a bit more polymer can be helpful, too.
pH Note. Keep in mind that if you add detergent or water to a mix whose pH has been adjusted (which we generally strongly recommend), you will need to readjust the pH if you add a significant amount of water or detergent to keep the pH in an optimal range.