Sand bed advice needed

[treesprite]

I emptied my 75g, except for sand bed, which I want to keep alive, without the tank being full of water. 

 

I have just enough water to know the sand is wet; deepest spot is 2".  I have air stones in it so it stays aerated and gently circulating. I need to keep it unfilled like this for the next year until I can move.

 

My concern is about salinity in the sand bed. Is it going to be stable just keeping the little bit of surface water topped off? It never occurred to me in the past, that I might need to have a better understanding of salinity-related sand bed processes.

 

The non sand bed-related info, is that I have all my liverock packed in the 50g sump and my 15H that I had to set up. They aren't plumbed together yet, but they could be, since the 15 has a 1" bulkhead in it (it's plugged atm).  I wanted to put up my 29 instead of the 15, but the 29 isn't drilled and I think it's tempered. Does anyone know if the 29s from PetCo are tempered glass? 

 

Thank you for any advice you have for keeping the sand bed alive.

Edited April 30, 2022 by treesprite

[Salty Rambler]

Are you moving only a short distance in a year? I've moved my tank twice -- once a 40 minute drive with sand in it, and once cross country without sand in it. If it is a longer move, and isn't happening for a year, you might consider just starting fresh with new sand vice dealing with the extra weight and potential mess of moving a tank with wet sand in it (and all of the detritus that the sand bed tends to hide). For what it is worth, I didn't notice a difference in tank stability when I went with new sand.

 

If you definitely want to keep the sand, I think your plan to top off the water is a good one. You might also want to explore gently stirring the sand occasionally, and researching whether high/low temps would impact the beneficial bacteria you are presumably trying to preserve.

[DaJMasta]

The kind of stuff living in the sand bed will likely be fairly durable - some swing in salinity shouldn't be too much trouble.  That said, the kinds of things in there will be sort of dependent on the depth they are at, so by mixing it up things have to reset to some degree already, so especially if you're looking for the larger top-of-the-sand-bed sort of life, maybe keep a lesser amount of sand alive and just leave it an inch or two deep - this way regardless of how you stir it, the things in it will be at about the right depth.  It's also more likely that such macro life will be more dependent on other things for food - so they're likely going to be on the live rock but not as much in long term stored sand.

If you keep a top on the vessel that has the sand, evaporation should be low even with airstones going, so you can just remember the water height and pour in a little RO to top it off and keep the salinity in the right ballpark.

[treesprite]

I just want to maintain the nitrifying bacteria.

 

The first reason I want to preserve the bed, is that it takes an eternity to establish a sand bed and I don't want to go through it again. The second reason is, I don't want to have to throw away all this sand when its roughly only a year and a half old.