Get extra prime for water changes. As you are going though this change, you are going to have to watch your parameters very closely, and may have to do a few extra water changes.
I don't use lava rock but it's old school method. Get about 200-300 pot scrubbies and trust me those things do wondersI'll go get some lava rock this am, and get that going in the sump, and start adding a little bit of tap water as well. Anything else you guys suggest to do today? Hopefully the bacteria grows quickly in the rock.
Any update?