Cleaning dead DSB

[bheron]

Hi all,
Sadly my backup generator broke during the recent snow storms and my tank was @ 45 degrees for 5 days. I lost all livestock and most of my Deep Sand Bed. I'm deciding to either A) keep and regenerate the DSB with the inhabitants still alive or B) nuke it and start over fresh...

My question for this forum is: If I go with option B how should I go about cleaning my DSB to remove all organic material?

My tank is 220g and the DSB is 4+ inches deep. I think thats around 7,000 cubic inches. Thats alot to clean. some approaches I can think of:

- remove it, rinse with water and then soak in something like sodium hydrochloride (LYE)

- keep it in the tank, dose with sodium hydrochloride, and then rinse all within the tank

thoughts?

[Jpugh73]

I would say start fresh to me that would be a big risk with a big tank and a lot of sand if something was to go wrong

[bertoni]

I'm sorry to hear about your problems.

You could try rinsing or bleaching the sand, but it's difficult to guess how much organic debris might be in the sand. If the sand bed was doing well, the sand might be fine with some rinsing.

[bheron]

thanks all. yea i'm really torn. i know there is still live in it. just dont know how much dead material there is. is that a bad omen to start a new tank on? i was thinking i would just keep exporting nutrients until it balanced out before adding any livestock. i hate to lose the diversity that still might be left alive.

[bertoni]

Personally, I'm patient and would wait for the sand bed to recover, but that could take months and require a lot if phosphate export, which can be pricey or take a fair amount of work.

[tmz]

I'd scrape off the first inch or so and ditch it. The stuff down deeper may be relatively clean if the bed isn't very old.

[nicholasb]

Remove the top layer and go for a shallow sand bed. Or remove the top layer and shift bottom sand to one side, and add new sand.

[bheron]

ok. the sand bed is probably a year and a half old. and from what i can tell it had tons of life and diversity in it. interesting in that i was dealing with a very bad Dino problem right before the crash, and was planning on draining the tank, cleaning the walls, and removing a top layer of sand. on the hope that the dinos didnt make it to the deeper layers.

i am leaning to keeping it alive and patiently trying to rejuvinate it with heavy nutrient export. figure the dead organisms will decompose and either be exported or seed the sand bed.

but...if i decide to nuke it and start over, i cant decide on a viable approach. removing and cleaning that much sand is a monumental task. leaving it in there and nuking it may mean i never get the chemicals out again.

[brad_G]

If you had dinos i would beach everything! Or maybe hydrogen peroxide. Heck I would do both. I'm telling you now if you don't sterilize everything you will regret it 6 months if something pops back up. At least nuking it you will know you did all you could.

I was all for let it go and recycle itself. Add some gfo and wait a month but if it were my tank with a dino problem I would nuke it.

[toothybugs]

Last time I had a problem I cleaned mine with bleach, washed it several times, and then baked it at 250 to drive off the moisture and neutralize the bleach (you can safely neutralize bleach with hydrogen peroxide too, but residual will kill bacteria in the future - heat takes care of both problems). Took a while, you have to agitate the sand to keep the moisture moving out of it, but the results were worth it - no phosphates or nitrates in the sand and it was easy to re-seed.

It was like buying dry sand and seeding it - quite literally starting new.

[bertoni]

If the sand is dead, or dead other than microbes, then discarding the top inch probably would save some time and effort. I'm not sure what might be live at this point.

[bheron]

If you had dinos i would beach everything! Or maybe hydrogen peroxide. Heck I would do both. I'm telling you now if you don't sterilize everything you will regret it 6 months if something pops back up. At least nuking it you will know you did all you could.

I was all for let it go and recycle itself. Add some gfo and wait a month but if it were my tank with a dino problem I would nuke it.

:-) see that's my fear and why I'm having a hard time here. But I'm more leaning towards the thought that, dinos may always be in my system and there are ways I should be able to suppress them with good husbandry. Altho none of them worked on my last tank! :mad2:

[bheron]

Last time I had a problem I cleaned mine with bleach, washed it several times, and then baked it at 250 to drive off the moisture and neutralize the bleach (you can safely neutralize bleach with hydrogen peroxide too, but residual will kill bacteria in the future - heat takes care of both problems). Took a while, you have to agitate the sand to keep the moisture moving out of it, but the results were worth it - no phosphates or nitrates in the sand and it was easy to re-seed.

It was like buying dry sand and seeding it - quite literally starting new.

Right, but I have so much. I think I put in 13 x 50lb bags of sand when I started it new.

[bheron]

If the sand is dead, or dead other than microbes, then discarding the top inch probably would save some time and effort. I'm not sure what might be live at this point.

Yep, I'm not sure either. When I got my power back I immediately restarted flow and heat. then I did an experiment. I raked the top 1/2 inch of sand clean, getting rid of all the tracks made by the critters. Then waited to see if new tracks were made. here and there I see new tracks. and I'm keeping a food source in there. so something is alive. I'm thinking if a small, but diverse, amount of critters are alive they'll reproduce again. thinking the dead organisms will decompose and have to be exported, or they'll be a food source for the ones still alive?

I've contacted Ron Shimek on this as well. Big decision I need to make.

[clay12340]

Scoop out a couple of cups from the surface and compare what is live vs what is dead. It should at least give you an idea of where you stand currently. I wouldn't be that terribly surprised to find out that a good portion of the critters in there made it. Water temps in a lot of areas get pretty cold in the winters, so a lot of the animals are probably pretty well adapted to seeing 45 temps. Hopefully the drop in temp happened slowly enough to allow them to survive.

Assuming it isn't just a complete mess of funky detritus I would be tempted to give it a little time at normal params and see how it is doing. The cost of fixing it if it is bad isn't going to change anytime soon, so worst case you wait and it still has to be done. Best case it self corrects and you save yourself the trouble.

[bheron]

Scoop out a couple of cups from the surface and compare what is live vs what is dead. It should at least give you an idea of where you stand currently. I wouldn't be that terribly surprised to find out that a good portion of the critters in there made it. Water temps in a lot of areas get pretty cold in the winters, so a lot of the animals are probably pretty well adapted to seeing 45 temps. Hopefully the drop in temp happened slowly enough to allow them to survive.

Assuming it isn't just a complete mess of funky detritus I would be tempted to give it a little time at normal params and see how it is doing. The cost of fixing it if it is bad isn't going to change anytime soon, so worst case you wait and it still has to be done. Best case it self corrects and you save yourself the trouble.

So how would I be able to tell what is live? would I need a microscope or something? Thanks so much, these responses are exactly why I come to this forum. Such great perspectives.

Totally agree, cant hurt to much to give it a go, measure parameters and look for reoccurance of Dino junk.

so I will:


make sure water temp is good and DSB has a food source.
Short term will put some dead shrimp or fish food in there, long term some small fish
Watch parameters specifically Nitrates and Phosphate
Peform nutrient export (skimmer, water changes, GFO) until measurements are zero
Watch for regrowth of dinos
Watch for trails in DSB


Should take a few months to be sure. best case I have a clean tank and healthy diverse sandbed with little effort. Worst case I'll have wasted onths and will still have to do a complete teardown and nuke the sandbed.

[clay12340]

For the tiny life not visible to the naked eye you'd probably need a microscope, but a lot of the sand bed critters are easily large enough to see with the naked eye or a magnifying glass. I'd think going through and looking at whether or not those critters are alive should give you at least some info to make a decision off of.

I don't think I'd worry about the fish food or shrimp for a little while. I'm sure some of the stuff has died off, and whatever is alive will be able to eat it. More than likely they've got an abundance of food at the moment. You also won't have to wonder if the nitrate and phosphate are coming from the rotting uneaten food or if it is coming from dead biomass in the tank.

I'd probably try to re-evaluate based on all the evidence every week or so. Once you get some trends from water testing and algae growth it should give you a better idea of what you're dealing with.

That at least is the approach I would take at first. Good luck and keep updating the thread so we can see how it turns out.

[bheron]

ok thanks. will be giving this a try and will post back.