Keeping a really deep sandbed clean with Garden Eels

[kazeespada]

I have been planning a garden eel garden for a while now. The plan is for an extra deep, nearly foot deep sandbed so even adult eels can submerge comfortably. One question I can't seem to solve is how to keep the sandbed from forming pockets of Hydrogen Sulfide. Most guides recommend stirring the sandbed, but that would destroy the eel burrows. What are other ways I can keep the sandbed from forming large Hydrogen Sulfide pockets?

 

[MantisShrimpMan]

I’m not an expert at this at all, BUT, I’ve done a bit of my own research on the matter (for a while I was looking at an 24x24x30 74G tower to make a garden eel garden) and have a few ideas.

Idea #1:
Minimize the overall amount of sand that’s present. Like, when you go to an LFS and see that there’s a plastic deli container filled with sand to support a tube anemone in an otherwise bare bottom or shallow substrate tank. You could use clever aquascaping so that the rock creates a dam whereby one zone in the tank can have a considerably deeper sandbed than the rest. Alternatively a dropoff style tank could accomplish the same thing. The eels will look for deep sand so maybe not right away, but even if it’s hidden I’d bet they’d eventually find the deep sandbed regions.

Idea #2: you need to pack your sand with organisms that will promote sand movement on an ongoing basis. One if not multiple pistol shrimp, jawfish, nassarius snails, etc. stuff that will go deep and make the most of the sandbed.

Idea #3: this is the most expensive idea IMO. Something akin to an under gravel filter but on a much larger scale. Either using consistent airflow to push out hydrogen sulfide pockets before they accumulate to such deadly points (keeping the sandbed highly aerobic) or alternatively, something akin to a dough hook on a stand mixer that occasionally activates. This would destroy the burrows, but garden eels can rebuild those pretty easily and it would totally stir up the sandbed.

Idea #4:
Just kinda live with the risk and see what happens?

idea #5:
Just use 4-8” instead of going to a proper foot thick, other people have managed to keep garden eels that way.

 

[kazeespada]

Idea #2: you need to pack your sand with organisms that will promote sand movement on an ongoing basis. One if not multiple pistol shrimp, jawfish, nassarius snails, etc. stuff that will go deep and make the most of the sandbed.

Idea #3: this is the most expensive idea IMO. Something akin to an under gravel filter but on a much larger scale. Either using consistent airflow to push out hydrogen sulfide pockets before they accumulate to such deadly points (keeping the sandbed highly aerobic) or alternatively, something akin to a dough hook on a stand mixer that occasionally activates. This would destroy the burrows, but garden eels can rebuild those pretty easily and it would totally stir up the sandbed.

Idea 2 and Idea 3 were the two ideas I was looking at. I did some research a while back, and sand shifting echinoderms(which normally don't do well in reef tanks) can put in some serious work.

Idea 3 was a reverse gravel filter. Although, I'm not really sure how to do one without turning the sandbed into a jacuzzi.

 

[vlangel]

I’m not an expert at this at all, BUT, I’ve done a bit of my own research on the matter (for a while I was looking at an 24x24x30 74G tower to make a garden eel garden) and have a few ideas.

Idea #1:
Minimize the overall amount of sand that’s present. Like, when you go to an LFS and see that there’s a plastic deli container filled with sand to support a tube anemone in an otherwise bare bottom or shallow substrate tank. You could use clever aquascaping so that the rock creates a dam whereby one zone in the tank can have a considerably deeper sandbed than the rest. Alternatively a dropoff style tank could accomplish the same thing. The eels will look for deep sand so maybe not right away, but even if it’s hidden I’d bet they’d eventually find the deep sandbed regions.

Idea #2: you need to pack your sand with organisms that will promote sand movement on an ongoing basis. One if not multiple pistol shrimp, jawfish, nassarius snails, etc. stuff that will go deep and make the most of the sandbed.

Idea #3: this is the most expensive idea IMO. Something akin to an under gravel filter but on a much larger scale. Either using consistent airflow to push out hydrogen sulfide pockets before they accumulate to such deadly points (keeping the sandbed highly aerobic) or alternatively, something akin to a dough hook on a stand mixer that occasionally activates. This would destroy the burrows, but garden eels can rebuild those pretty easily and it would totally stir up the sandbed.

Idea #4:
Just kinda live with the risk and see what happens?

idea #5:
Just use 4-8” instead of going to a proper foot thick, other people have managed to keep garden eels that way.

I have a tank with tiered levels of sand. I like DSBs (deep sand beds) and the last 3 of my 4 tanks have had them. I worked as a lfs and took care of their aquarium accounts in private residences and businesses. My boss always set up DSBs. I know of some of those tanks are still going strong in their original set for 20+ years without any poisoning incidents. One of the accounts became a very good friend and she has fish that are also 10+ years and one Emperor Angel that is the size of a dinner plate.

In my opinion the risk of poisoning by sulfide gasses is over blown. A well set up DSB with nassarius snails, maybe a cucumber after it is established and fish that will stir the surface but leave the deeper anaerobic areas alone and intact can last decades. I would not be afraid to keep garden eels in a tank with a 10"-12" sand bed if it was properly set up.

You can see

 

[ISpeakForTheSeas]

Just to add some potentially helpful care info for anyone curious:

For garden eels, most people seem to struggle with them, but the person I’ve quoted below had them breeding in their tank (as of their last post in the thread, haven’t been able to get the young to settlement yet):

As far as my broodstock goes. (If my phone autocorrects that one more time to broomstick, I will scream!!!) I have 5 adults, 3 male and two females in my seahorse tank. They eat literally everything I put in there, including flake food. But they eat mainly a diet of PE mysis and whatever bits of the Gamma Marine Cuisine they fancy. SG 1.023, temp 22-23degrees Celsius. Sandbed of minimum 4 inches, rising to about 6 at the back. But they're happy in the 4" at the front.

The eels are some of my oldest tank residents, I've had a tank wipeout that these guys survived. I've had 3 (including the breeding pair) for around 5 years and two others for about two years. They eat literally everything I throw at them, including flake food and pellets. But because of the seahorses, they get mainly frozen food. But again, only twice a day. The biggest problem with garden eels is them escaping. My tank has a brace around the inside that's about 3" wide, there's a gap for the return pipes which I fill with filter floss because they will literally get through the tiniest gap, but only at the edge of the tank. I think the brace on mine is what's saved many of them from the carpet, unfortunately I've lost two newcomers from forgetting to fill around the return pipes with filter floss.

I feed the whole tank one cube of frozen gamma mysis, one cube of gamma marine cuisine and one cube of PE mysis, twice a day. The garden eels eat anything that comes near them, even the huge bits of mysis and happily take flake food too.
The shrimpfish prefer the mysis and aren't shy about competing with everything else for it.
I don't regularly add rots/pods or phyto to the tank. Just chuck some in every now and then if I have a surplus. The seahorses, copperband, filefish and mandarin means I don't have a large population of pods/mysis anymore.

I don't know if they're happy because of the other slow moving/careful feeding fish in there or because of the temp/salinity/rock placement etc. I keep the tank and 22-23degrees year round, SG at 1.022-1.023 and do about a 30% water change every 10-14 days.

Maybe I just got lucky!

 

[MantisShrimpMan]

Hey I saw something on Facebook marketplace that might be relevant to this brainstorming session. Someone near me is selling a 100 gallon lobster tank. The reason I bring this up is because the design might be advantageous to a limited DSB usage.

So the tank is 4 panes of glass, but instead of a 5th pane of glass serving as the bottom, its on top of this thing that looks like a bathtub, can't tell whether its plastic or ceramic. That hides the cross section of the sanded from being visible, so you won't have the "well the detritus looks like crap" effect, and also minimizes the overall footprint of the area with deeper sand.

So like, to take this principle a step further, what would happen if you found an acrylic tank manufacturer who could make you an internally recessed drop-off tank? internally recessed meaning that no pane of deeper drop off is visible from the sides, like this:

That way, you conceal your detritus bed so it's not really aesthetically bothersome, and also you cut down on the footprint of sand needed. It would be hard to build a stand for this maybe? idk.