Do you clean your sand bed?

Just to weigh in, I wouldn't touch your sandbed unless you have crushed coral, which you should vacuum. Never simply "stir up" your sandbed, as even shallow substrates can have anoxic layers in them, and there are compounds in those areas that you DON'T want in your water column. I've seen entire tanks killed off by having the substrate stirred.

As for water changes, weekly is fine if it works for you.

 

God this post scares me.. I'm upgrading to a 75 and going to pink Fiji sand. Nice post and good info!

 

As long as the sandbed is say 2" or less it will not support the beneficial anoxic and anaerobic bacterias that contribute to denitrification and will cause problems when stirred up and exposed to oxygenated water. Stir it or vacuum it all you want. If the sand is approacing 3" or more it is considered a DSB or deep sand bed and it should be left alone using a clean up crew to cleanse it naturally so you do not disturb the bacteria down deep.

My 100G mixed reef is almost 10 years old with a 330 lb. Southdown 5-6" deep DSB and never been vacuumed or touched in any way with the exception of the top 1/4" and only in small sections at a time so nothing is disturbed. The nitrates and phosphates are both undetectable using Salifert kits and all is well.

 

In theory, you're correct, but I've seen stirred SSB's nuke tanks...more than once...why chance it?

 

I appreciate all the replies! My main thing is, we really want corals. We had an amazing mixed nano a few years back. Now that we have this bigger system that has been up for 9 months, we want to add corals now. We are going to a frag swap in 2 weeks, so we're most likely coming home with corals. But, that is what I bought one mushroom and one clove polyp to, "test" my tank. I'd hate to buy LPS, soft and maybe SPS coral, just for them all to die. I use RO water, so I thought that maybe having low PH would make it hard to keep a reef. Btw, my clove polyp has not opened at all yet and the mushroom I see every few weeks when it floats around. So, so far I'm concerned. We've got to have our disc coral, among many others.

 

As have I, and I would never chance it with a deeper sand bed. The sad thing is that once the noxious substance were released nothing could be done to save the tank. Water changes were of no benefit, running carbon did no good, it was simply a death sentence for the tank.

And I have seen older sandbeds moved in their entirety with no issues at all.

This has always baffled me.

 

And I have seen that too but it goes further than stirring a sand bed, its the lack of maintenance and build up over time then all of a sudden stirring it to make up for all the maintenance you did not do for years. Regular stirring and vacuuming will not do this if it has been done since new, don't do it for a year then stir and all bets are off.
As I mentioned before, even with a shallow layer it is better to clean a section at a time than to do it all at once, theory or no.

 

I have about an inch to inch and a half sand bed that is a mix of sand and crushed coral. I vacuum with a siphon in most exposed sections each water change. I do a water change about ever three weeks to a month of 20%. My tank is a 54 gallon corner tank.

I think I would be apprehensive about stirring up the whole sand bed but would think siphoning sections may be a better way to go.