Munroco said:I'm not sure what SW and FW are but I collected the bricks at Westhaven, which is between Carnoustie and Arbroath. (East Coast of Scotland for those not familiar with these places) I've been keeping an eye on parameters. These things look to have been in the sea for years. I expect them too leach a little but nothing excessive (I hope). I probably needed them to bump up my GH and KH.
FW being Freshwater and SW being Saltwater.
What I meant was in what area did you find these bricks in but you have just answered that anyway. I am just a little concerend that these bricks may have absorbed some salt or pathogens over the years of being in seawater.
And shrimps do not like salt.
So hopefully, these bricks are totally inert and have not absorbed anything at all or at worst just a trace amount that will not do any harm at all.
Like I say, keep a close eye on the water stats as bricks tend to be made of fairly soft materials and may break up being in water 24/7.
I would always be very cautious about putting in wood, decor or stones from the sea into a freshwater tank.
Am probably being far too cautious here and being a little too pernickity.
Anyway, crystal shrimps are real nice and I wish my water was suitable for these guys. A little more info on these cute guys - http/www.planetinverts.com/Crystal%20Red%20Shrimp.html
Good luck