New 55

[southernmost]

Ok I'll admit it I messed up. Set up all my tanks with large River rock from Home Depot. Looks great but I think my shoals of Cory's and clown loaches will eventually injure themselves while feeding. Rocks are a little bit smaller than a dime but the 120 is already cycled and fully stocked, one 55 has 12 breeding pairs of fancy guppies and the two 29 quarantine tanks are in use. How do I get the gravel out without completely ruining the cycles or harming the fish? Want to go fully planted in all but the quarantine tanks. Should I fill the new 55 with the water and fish from the tanks that need new substrate or try to redo while up and running? Tried to go cheap and I'm paying for it now!

 

[cgthebeast]

Actually the substrate holds very little BB, gravel does hold more BB them sand but the filter holds most of it actually. What you need to do is take a little out at a time and replace it with the substrate of your choice. If you go with sand, it probably will mix with the rocks but won't be as bad. You could fill the 55, move the filter over to it. Scoop everything out, and full with new substrate, also but all the big decorations in the new tank as they hold bb also, you might gave a mini cycle but nothing a water change can't fix. The filter should've able to hold all the bb for your stock