Looking for advise on upgrading from a 90g to a 180g. the last time I upgraded from a 90g to a 240g I just made up more salt water and moved everything to the 180g. This time I want to replace all the rock with dead rock islands that have been bleached and acid cleaned. I would probabally put a rock or 2 in for seeding and mix up the balance of salt water. The first tank upgrade worked well but used existing rock work with some additional added. I want to make sure to do the right thing on this upgrade. The reason for not using the old rock is phosphate leaching. I want to do the right thing on this upgrade so any and all opinions and experience are appreciated. Thanks, Doug

