Swapping out sand in established tank

buercky · Aug 13, 2016

I have a inherited a 14G Biocube from a coworker. The tank has been up and running with a lone clownfish for about 10 years. I've added a blennie and CUC. Its been a little neglected and had a ton of GHA and the sand bed I'm sure is loaded with who knows what. I've gotten the GHA cleaned up and peroxided a good portion of the rocks to also get rid of the GHA on them. Anyways I'd like to somehow get that old sand out and replace with new. Its setup with I would guess 10-15 lbs live rock, bioballs, and about an inch of sand.
How would I replace the sand?
Can I put the rocks into a bucket of tank water with the clown, blennie and cuc, remove all the sand/muck and replace with live sand?
Do I have to cycle the live sand?
I don't have any other tanks that I can QT everything until its back.
Thanks for all the help!

Starting

Now

mcarroll · Aug 13, 2016

Use a 1/2" or 3/4" tube to siphon out the sand.

If the rocks are up on the sand you'll have to manage them somehow during the process...in the bucket or otherwise.

Don't repeat that mistake - stack the rocks on the bottom glass and IF YOU DON'T KEEP THE TANK BARE BOTTOMED. Then you can just add sand around them.

As long as you're adding clean sand (no critters in it or dirt) then you can just add it and forget it....no curing.

What you DO WANT TO DO is remove the sand in stages....about 1/4 of the sand bed per week.

This gives a chance for the bacteria in the rock and elsewhere to grow and make up for what you're about to remove - you could get an ammonia spike if you just removed all that bio-filter at once.

wkscott · Aug 13, 2016

Duplicate.

brandon429 · Aug 13, 2016

Ten examples of bed swaps and moves plus opinions on what to do with your new bed etc
http://reef2reef.com/threads/the-of...ead-aka-one-against-many.230281/#post-2681445

We made that thread because it's nice to see others leap off the diving rock first, a tank reboot is loss risk