I've been to bridlington and while i was there i pick a few white pebbles off the beach. I have gave them a good wash and a lot of white stuff came out of them, i think it was salt from the sea. What i would like to know is are these pebbles safe to put in my tropical fish tank. any help, thanks.

It depends what type of stone the pebble was made from. Chalk, sandstone, granite, etc all leach different elements into your water, and depending on what type of tropical fish you have will also determine the type too.

i have never really had any issues, i kept cichlids and i used to bring pebbles from beaches all over to put in but i boiled them up first.

We have just done the same thing (back from holidays with rocks) - we asked at the local fish shop who said that if they were boiled vigourously for about 10 minutes they should be OK. Going to try this weekend.

as a guide i used to put a little viniger on the rock/pebbles to see if there was any reaction . if no reaction i would wash them & use them ,if any reaction i wouldnt use .i.e if i remember right if you put vinger on sandstone it would disolve the stone so dont use

Thanks for all advice. I've boiled the rocks up for 1/2 hour and have now had them in tank for a couple of days. all seems well. thanks again.