Robert M
Non-member
So I finished converting my old 120G to my new sump, complete with custom glass baffles I installed myself. I was careful to pick out 100% silicone that did not list a fungicide, pesticide or mold inhibitor in the ingredients and did not say “not safe for aquariums” on the label (it didn’t mention aquariums at all).
After a full one day cure I checked the baffles (seals look great) and happen to notice the silicone says “mold resistant for 20 years” on the label. Wait a minute, I think. How can silicone be mold resistant without a mold inhibitor?!? So I look up the safety data sheet using the product UPS code and find an extra ingredient that was not on the product label “hydrotreated middle distillate”. Sounds benign enough. More digging and I find EU safety data on that ingredient. It’s a pesticide! (Darnit!). I estimate I put in 7mg of the stuff in my silicone, which is about 1/1000 the toxic amount over a 72 hour period for my size tank. However, as I’ll have my sump installed for perhaps 1000 times longer than 72 hours, I figured it’s not worth risking.
So this weekend instead of installing my new sump, I’ll be ripping it back up again, removing all the old silicone, and starting over with an aquarium safe product.
Who said this hobby wasn’t fun?
After a full one day cure I checked the baffles (seals look great) and happen to notice the silicone says “mold resistant for 20 years” on the label. Wait a minute, I think. How can silicone be mold resistant without a mold inhibitor?!? So I look up the safety data sheet using the product UPS code and find an extra ingredient that was not on the product label “hydrotreated middle distillate”. Sounds benign enough. More digging and I find EU safety data on that ingredient. It’s a pesticide! (Darnit!). I estimate I put in 7mg of the stuff in my silicone, which is about 1/1000 the toxic amount over a 72 hour period for my size tank. However, as I’ll have my sump installed for perhaps 1000 times longer than 72 hours, I figured it’s not worth risking.
So this weekend instead of installing my new sump, I’ll be ripping it back up again, removing all the old silicone, and starting over with an aquarium safe product.
Who said this hobby wasn’t fun?
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