# Thermometer broke in tank



## jeff12 (Oct 21, 2011)

I was cleaning my fish tank and my thermometer got smashed. I had those thermometers when there was a orange, black thingy that surrounded the mercury. The mercury part is not broken but there are little black balls that dropped into the gravel. Are these black balls harmful? Should I do a water change?


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## The Cichlid Guy (Oct 18, 2014)

I had this happen in a tank last year. The balls can be removed with a magnet in a Ziploc bag. I wouldn't try to siphon them out, as they are pretty heavy, and you'll likely remove a lot of gravel and lose the balls in the tank. I'm not sure about the toxicity of the balls over time, though.


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## jeff12 (Oct 21, 2011)

Did any of your fish die or anything?


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## pfoster74 (May 13, 2012)

i had a heater blow up once and took me a long time to find all the glass good luck and i would try to remove the balls if possible not sure if they will be toxic but i wouldnt risk it.


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## Deeda (Oct 12, 2012)

Aquarium thermometers use a non-toxic liquid, not mercury, so no problems. The balls, or weights can be removed using a magnet if they are iron and scooped out if they are lead, neither should cause problems with your tank. Any glass shards should also be carefully removed using a net or utensil.


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## JP_92 (Aug 2, 2013)

I read this thread yesterday and it completely jinxed me. Was putting away my hospital tank and wouldn't ya know it my nice thermometer smashed to the floor. Picked up the balls with a piece of shipping tape and was snappin' mad thinking about what just happened and this thread.


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## pfoster74 (May 13, 2012)

if you don't break something every once in awhile you aren't living right.


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## beachtan (Sep 25, 2008)

I would DEFINITELY do everything you can to get all the little balls out of your gravel. I only scooped the ones on top of the sand out and over time, the ones I missed grew into rust pieces that looked like crumbled lava rock - some have adhered to the bottom glass and wont come off, the others keep working their way up to the surface where the fish mess with them. I lost a prized fish who was nosing around that area and the only thing i can figure is that he sucked one up while sifting sand.


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