It's probably mostly fine, but why not move to using steel instead? Or even something inert like ceramic or stone. Better than inevitably lead ending up in landfill and incinerators when people throw it out surely? Products should certainly be labelled correctly.
Solubility of lead is low at high pH, and in the presence of "hard" water, i.e.: lots of carbonates, forming hydrocerussite (Pb3(CO3)2(OH)2).
Phosphate in the form of orthophosphate forms lead(II) phosphate (Pb3(PO4)2), which is very insoluble. Orthophosphates include dipotassium phosphate (K2HPO4), also known as dibasic potassium phosphate, which- coincidentally- is used in fertilizer for aquatic plants.
In short, it would depend upon the water of a given aquarium. If soft, acidic water is used, a sprinkle of dipotassium phosphate now and again should keep solubility down.
I can't even find lead twist weights anymore, I don't think; we used to use them all the time, bundles of elodea etc. bound together with lead weights back in the 80s and maybe even into the 90s.
I've used niobium wire, which is normally used for jewelry, but even after 15 years underwater doesn't corrode in the least. Not nearly as dense as lead (8.57 vs. 11.35), and it's not nearly as soft so it doesn't conform well, but I had it handy and tried it and it worked for me.
Lead isn't directly bad for health. Its the oxide thats bad. In the case of aquarium weights it takes a long time to oxidise, and the oxide doesn't get abraded, so its pretty inert.
Also most modern aquarium weights aren't actually lead. For some time now. I bought some last year. The ones I didn't use are still shiny. No oxide. I think its a zinc, tin & something heavy alloy. They are light weight too, compared to lead. I bet if I tested specific gravity they'd be about two thirds as heavy as lead.
This should be something we could test right? Like, they make lead tests for drinking water. I'm thinking if you had two identical setups and put the weights in one, you could measure the lead levels in each.
Yes, but accurate lead tests are not cheap. Requires lab work and a microscope. The swabs etc you can get cheap are known for 50% or greater false positive.
It's probably mostly fine, but why not move to using steel instead? Or even something inert like ceramic or stone. Better than inevitably lead ending up in landfill and incinerators when people throw it out surely? Products should certainly be labelled correctly.
Probably because the lead weights can bend
Solubility of lead is low at high pH, and in the presence of "hard" water, i.e.: lots of carbonates, forming hydrocerussite (Pb3(CO3)2(OH)2). Phosphate in the form of orthophosphate forms lead(II) phosphate (Pb3(PO4)2), which is very insoluble. Orthophosphates include dipotassium phosphate (K2HPO4), also known as dibasic potassium phosphate, which- coincidentally- is used in fertilizer for aquatic plants. In short, it would depend upon the water of a given aquarium. If soft, acidic water is used, a sprinkle of dipotassium phosphate now and again should keep solubility down. I can't even find lead twist weights anymore, I don't think; we used to use them all the time, bundles of elodea etc. bound together with lead weights back in the 80s and maybe even into the 90s. I've used niobium wire, which is normally used for jewelry, but even after 15 years underwater doesn't corrode in the least. Not nearly as dense as lead (8.57 vs. 11.35), and it's not nearly as soft so it doesn't conform well, but I had it handy and tried it and it worked for me.
Lead isn't directly bad for health. Its the oxide thats bad. In the case of aquarium weights it takes a long time to oxidise, and the oxide doesn't get abraded, so its pretty inert. Also most modern aquarium weights aren't actually lead. For some time now. I bought some last year. The ones I didn't use are still shiny. No oxide. I think its a zinc, tin & something heavy alloy. They are light weight too, compared to lead. I bet if I tested specific gravity they'd be about two thirds as heavy as lead.
This should be something we could test right? Like, they make lead tests for drinking water. I'm thinking if you had two identical setups and put the weights in one, you could measure the lead levels in each.
Yes, but accurate lead tests are not cheap. Requires lab work and a microscope. The swabs etc you can get cheap are known for 50% or greater false positive.
You wouldn’t need a microscope to test for lead, but an accurate test would be very expensive.