Help Troubleshooting Bath Bombs

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Feb 3, 2015
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I've been making a variety of bath bomb recipes for the past month now and have had some success and some fails. I'm hoping someone out there has some tips that can help out.

Basic Recipe
1 cup baking soda
1/2 cup citric acid
1/2 cup epsom salt
1/2 cup oatmeal flour
2 tbspn coconut oil
essential oils
witch hazel

Problem 1: Bath bombs develop tiny little white spots after they've been packaged for a couple of days.

I assume this is due to the humidity in the air and when I shrink wrap them, the moisture gets trapped inside and causes the reaction. I don't fully shrink wrap my bombs, just the bottom half is shrunk so I can still tie off the top and people can take the bombs out with their hands. Has anyone else had this problem? My bombs look great when I package them, I picked up a few yesterday and noticed they had all the little spots. I also considered maybe the spots are because I didn't sift the ingredients well enough.

Problem 2: Bath bombs don't float
I pack them in pretty tightly and get about a 6.5 oz ball from a 70mm mold. I suspect it is the weight of the bomb that causes them to sink.

Any help would be appreciated!
Honestly I think the white spots are the oatmeal that has dried out.

As for not floating, I think the baking sodas reaction to the citric acid causes the float. So that means the reaction is not strong enough to cause the float. This could be that you added too much witch hazel and the reaction has taken place in the bowl, or ( what I really suspect) you have too much "extra" stuff in there. A full cup of salt and oatmeal.

You could either reduce the salt and oatmeal or increase the baking soda and citric acid.

I do make 7 oz bath bombs that float so I know it isn't the weight.
Thanks for the advice!

I wondered if it was the oatmeal in the bombs too, but the first few of the batches I made using the same recipe never got any spots. I did another recipe where I didn't use oatmeal and just cornstarch with the epsom salts and I got little spots all over my balls while they were drying overnight. That's why I started to wonder if it was the rise in humidity recently that is causing little reactions in the bombs.

I had my smaller bombs float with the same recipe. Then I read on SoapQueen that most bath bombs don't float if you pack them in too tightly so now I wonder if I should just try packing them less tight.

These bombs are the bane of my existence. I seriously dream about them floating and fizzing.
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its corn starch people add to the bombs that make them float.

the fizzing can make it float a little, but it wont float nearly as much if you dont use corn starch. but corn starch can give a person yeast infections.
I use oatmeal in mine and they dont have white specs. Also, mine are large 6.5 to 7 oz. and they float well. I think you probably need to add cornstarch, and as well be careful if you are spritizing with witch hazel or water to not use too much.
Here are mine....all have oats in them along with clays, etc.



its corn starch people add to the bombs that make them float.

the fizzing can make it float a little, but it wont float nearly as much if you dont use corn starch. but corn starch can give a person yeast infections.

I don't think that is true. I don't use any corn starch in my bath bombs, but they all float and fizz around the tub.
I don't think that is true. I don't use any corn starch in my bath bombs, but they all float and fizz around the tub.

yours float at the very top of the water? what else do you put in it?

I am having a major problem with bath bombs. I purchased a 50lb bag of citric acid. When it came it was granules (like table salt). I had been using a powder form with great results (but you can't buy in bulk quantity). Now my bombs won't stick together at all. I have tried everything. I finally grinded it down in my food processor and that worked fine but I don't want to have to keep grinding the citric acid every time (too time consuming). I can't find anything where other people are having any problems with the granular citric acid. Nobody else has to grind theirs in a food processor. I have spent several days on this and now I'm behind in production. Any advise?????? :oops::oops:
my citric acid is granules like salt/sugar. i have not had problems with it sticking together. maybe you just need more liquid. i used some oil and then spritzed alcohol in to add more moisture if needed. i find spritzing with witch hazel triggers more fizzing.
what do you put in your recipe? i put 1 cup baking soda, 1/2 cup citric acid, 1/2 cup salt (normal size granules) and sometimes milk powder (1/4 cup) and 1/2 oz oil. that amount makes about 3 bombs.
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I've used almost a 1/4 of a bottle of witch hazel spritzing the stupid batch. I have also tried water. Surely I shouldn't have to use this much or more?
dont use water! it will just make it fizz

try my recipe and spritz with alcohol. see if that works. if not, i have no idea.

the oils i use are cocoa butter or coconut oil
I've never used water before (shows how desperate I was). LOL

2 Cups Baking Soda
1 Cup Citric Acid
1 1/2 Tbsp Kaolin Clay
1 tsp Mica Powder
1 Tbsp Shea Butter
1 Tbs p Almond Oil
1 Tbsp Fragrance Oil
Witch Hazel

This recipe works great if it is citric acid powder. Doesn't work if it is granules.
did you try letting it rest in the bomb maker for a bit before removing it? what mold are you using?

maybe its just more delicate with the granules
i have not used fine ground citric acid so i cant compare.
I have a machine hooked up to an air compressor. It won't stick together. One half is in the bottom of the mold and the other half is stuck in the top half of the mold. I have to scrape it out from the top.

this lady had the same problems with a bomb maker


maybe her issue was granulated citric acid as well
with the machines maybe you have to have a fine powder....
I can understand your frustration when I see the video, haha.

Vmakkers, what kind of essential oils are you using as a fragrance? Might that be the problem when it is developing the spots afterwards?
Could you pop up a picture of the bath bombs as well so we can take a look at those spots?
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I don't have spots on mine. They look great when they stick together. When I use the citric acid granules, they won't stick together to form a bomb. It only works when I use citric acid powder.
I use citric acid in the granule form and haven't had an issue with warts or bombs that don't want to stay together. I do use the ornament molds like Ariane was in the video for my round bombs. The only issue I've run across is my bombs "growing" out of the fun molds sometimes, but I'm fairly certain that's too much moisture. Holly Port's recipes have generally worked out pretty well for me, too, even with substitutions.