Varnished Pebbles

[shiftingsands]

Hi all,
I bought some varnished pebbles with the idea to put them in the tank and wondered if they were safe for the fish? If its a bit doubtful, could I paint yacht varnish over the top of the present varnish? I read elsewhere on here that you could use yacht varnish when making back grounds, so I guess thats safe to use?
Thanks

 

[emma12321]

Hi,

Are the pebbled definately varnished ? i bought some polished pebbles which are very smoot and shiny but not varnished. The ones i got were from morrisons, buy one get one free for a small net with about 12 pebbles in. They are just decorative pebbles and were on the aisle with candles and stuff, i soaked them in boiling water for about an hour and they have been in all my tanks for over 2 years no probs. Not sure about varnish, see if you get more replies.

Emma

 

[shiftingsands]

Thanks Emma, No, I'm not certain they are varnished but as they were so shiny I assumed they were. Maybe they are just highly polished. I'll go back for some more and check it out.

 

[The Glassblower]

Marine paints usually have poisons in them as anti-fouling agents. It prevents alge from growing on the hull. I would worry about using it.

 

[Lateral Line]

A lot of those "shiny" stones you see are just polished. You place the stones in a drum with some water and progressively finer grades of Silicon Carbide abrasive, typically 3-4 grades. The drum then sits on a small electric machine which causes the drum to rotate and the stones to tumble over each other. They get smoother and smoother. To finish, you tumble them again with Cerium Oxide which does the final polish.

On reasonably smooth beach pebbles, each tumble with a grade of abrasive takes 7-14 days. I have such a machine, though as it is a little noisy in the house. I lent it to my friends on another island that have a big barn, it runs in there.

If the stones you have purchased are these, (likely), they are quite safe to use, providing you follow the usual rules for putting stones in the tank. They should not fizz if you put vinegar on them, and they should not be overly "heavy", (i.e. noticeably heavier then other similaly sized stones). The third criteria, they should not have sharp edges, is probably redundent in this case!

 

[OohFeeshy]

I've used the round shiny ones you buy in fishtanks, no adverse effects whatsoever. Although depending on what they're for its fa cheaper just to get a bucketful of rocks from the beach.