Tell me about deep sandbeds/ removing mechanical filtration

[duberii]

I'm pretty sure grass shrimp are basically predators.

That's a shame- I was hoping I could make it work. After a quick google search, I found that they feed on "algae, crustaceans, and worms" -definitely no good. Looks like my frogfish will be eating amphipods for a while until I can figure this out - it's still small so it's a nonissue, but I was hoping I could just add these grass shrimp without causing any issues.

 

[duberii]

I know I haven't started my salt water tank yet but both of my fresh tanks are DSB. This series of videos really help me understand and set up my tanks in this way. He uses the term no water change but I think the idea is the same. Here's the series: Jay's aquarium - YouTube. I'm going to be doing my EVO 13.5 with DSB. I love this kind of stuff too.

I have been watching newyorksteelo- he has some videos that seem to be more specific to DSBs, though less scientific. There are a few videos about hydrogen sulfide which I found interesting. Now I have more content to binge haha

 

[garbled]

Looks like my frogfish will be eating amphipods for a while until I can figure this out

So you could add them as food items, sure. I just don't think you want to try to setup a population of them.

IIRC, the general rule was: "All shrimp are predators, we just allow the peppermint ones in because they also kill aipstaisia". If you want some ornamentals, just be aware of their impact and compensate for it.

 

[jda]

Late to the thread, but most people who struggle with deep/deeper sand beds, usually were bad on their maintenance and then the sand could not cover up the issue for them. Sand, as all aragonite, binds phosphates. It does not do anything in a nefarious way, but this is just science/chemistry 101. Eventually, if the hobbyist is lax on their maintenance, knowledge or something, the sand will bind a lot of phosphate and the water level will fill up. These hobbyists will blame the sand for leeching or something bad when indeed they were the bad ones that did not do their maintenance.

The people who had success with sand likely did their maintenance and the ones without did not.

I will always use sand and Dr. Ron was very on the money with most things, but I feel that he missed on these few...
1). 3" is fine enough to get deep level of anoxic regions for nitrate to turn into nitrogen gas. No need for 6 inches.
2). It needs cleaned every 3-4 years. The stuff in there is benign long stripped of anything of value, but the benign stuff does "gum up the works" and keep microfauna from being able to penetrate and live there. Starting in about year four, I vacuum all the way down small parts of the sandbed (like 20%), then wait a few months before doing more.
3). Not a Dr. Ron miss, I run a fuge to keep P down so that my sand does not "fill up" with it. I like that is a buffer that never lets me hit zero, even though the tank keeps is very low.

My sandbed has always keep my nitrate about .1 to .2, which is plenty. I love that I don't have to think about or mess with it. I use some cucumbers (Florida Keys Yellow Variety), some snails (ceriths) and a few conchs (Keys Variety) that like to rummage around in it. The cucumbers will spilt/divide and come to a nice equilibrium with what is available for them to eat. The inverts that live in the sand are sensitive to high phosphate, so this makes it even worse when the sand cannot hide the hobbyists lack of maintenance anymore since they die too.

I have never had any hydrogen sulfide.

As for pods, you should be able to grow these with just about any kind of situation.

 

[vlangel]

That is such a cool tank! I notice you have some feather duster worms- do you feed them, or does the microfauna handle that for you? I would love to pick up some filter feeders for my tank but I'm trying to avoid needless casualties.

Thank you for the kind words. This type of tank is not everyone's cup of tea but I love how easy it is to care for. I love having a lot of fish too.

I never had luck with feather duster worms in the past but 4 of the worms have been with me about 12-18 months, and one of them has been with me for probably 2 and a half years. They seem to be flourishing so I bought some more for a whole garden of them. I am sure the microfauna is helping but I also feed heavy including frozen every day. I never rinse the frozen cubes either, like mysis because that juicy liquid is probably good food for the filter feeders. I also have 2 thriving scallops that hitchhiked on a piece of rock given to me by a reef friend.

 

[duberii]

Thank you for the kind words. This type of tank is not everyone's cup of tea but I love how easy it is to care for. I love having a lot of fish too.

I never had luck with feather duster worms in the past but 4 of the worms have been with me about 12-18 months, and one of them has been with me for probably 2 and a half years. They seem to be flourishing so I bought some more for a whole garden of them. I am sure the microfauna is helping but I also feed heavy including frozen every day. I never rinse the frozen cubes either, like mysis because that juicy liquid is probably good food for the filter feeders. I also have 2 thriving scallops that hitchhiked on a piece of rock given to me by a reef friend.

Nice! I always wanted a natural looking tank- I think the nice fluorescent corals in a reef tank look just as good as a nice brown and pink reef with highlights of macroalgae and anemones and such. If I had the room (and money frankly) I'd have a natural tank. Best of luck with all your filter feeders! I hope they continue to do well

 

[duberii]

Late to the thread, but most people who struggle with deep/deeper sand beds, usually were bad on their maintenance and then the sand could not cover up the issue for them. Sand, as all aragonite, binds phosphates. It does not do anything in a nefarious way, but this is just science/chemistry 101. Eventually, if the hobbyist is lax on their maintenance, knowledge or something, the sand will bind a lot of phosphate and the water level will fill up. These hobbyists will blame the sand for leeching or something bad when indeed they were the bad ones that did not do their maintenance.

The people who had success with sand likely did their maintenance and the ones without did not.

I will always use sand and Dr. Ron was very on the money with most things, but I feel that he missed on these few...
1). 3" is fine enough to get deep level of anoxic regions for nitrate to turn into nitrogen gas. No need for 6 inches.
2). It needs cleaned every 3-4 years. The stuff in there is benign long stripped of anything of value, but the benign stuff does "gum up the works" and keep microfauna from being able to penetrate and live there. Starting in about year four, I vacuum all the way down small parts of the sandbed (like 20%), then wait a few months before doing more.
3). Not a Dr. Ron miss, I run a fuge to keep P down so that my sand does not "fill up" with it. I like that is a buffer that never lets me hit zero, even though the tank keeps is very low.

My sandbed has always keep my nitrate about .1 to .2, which is plenty. I love that I don't have to think about or mess with it. I use some cucumbers (Florida Keys Yellow Variety), some snails (ceriths) and a few conchs (Keys Variety) that like to rummage around in it. The cucumbers will spilt/divide and come to a nice equilibrium with what is available for them to eat. The inverts that live in the sand are sensitive to high phosphate, so this makes it even worse when the sand cannot hide the hobbyists lack of maintenance anymore since they die too.

I have never had any hydrogen sulfide.

As for pods, you should be able to grow these with just about any kind of situation.

What if the sandbed isn't aragonite? Have you had any issues with the sandbed fusing and solidifying? That seems like the concern with aragonite sand. As for your first point, is there any benefit to going deeper then? My guess would be that the deeper sandbed would lower your nitrates even further, since more anoxic bacteria yields more nitrogen gas? Just a guess.

I would need to invest in a siphon with a longer tube, since even cleaning my bed can be irritating since it sucks up so much sand into the bucket. Mine is currently only about 6" but I have certainly seen longer ones. Got a recommendation? (a bit of a divergence but somewhat relevant)

Also, those yellow cucumbers are filter feeding, right? Do you think they survive off microfauna or something you're feeding the tank? I've always wanted a cucumber but I'm terrified that it would starve.

 

[chadfish]

I love this explanation and it did clear a few things up. My question is: What specifically in a plenum? A DSB is just a 6" or so layer of sand. From my understanding, a plenum is just the area under the sand (which I have no idea how possible that is- i guess your nylon layer is a good idea, but I think i need a visual for what a plenum is). Would water flowing from underneath the sand destroy any possible anaerobic zone? That way there's a constant flow of water supplying oxygen- correct me if I'm wrong. Could I just use play sand (is it fine enough?) for that middle layer? I have this aragonite sand (link) that I could use on top, then the play sand could be deeper?

I do stir my sand bed from time to time, and I siphon it every time I do a water change, but I can't help but feeling like there's a ton of detritus mixed into the sand that I can't get out without a more thorough cleaning.

Perhaps a hanging rockscape (hanging from the back of the aquarium) could keep the rockscape clear. Another possibility is that haveing chaeto or some other type of algae tank would get around the issue, but that's not always the most attractive tank.

When I set up my plenum on my 75 gal, I used a sheet of plastic grid used as a diffuser for fluorescent lighting. It was about an inch thick. I must have put mesh screen on top to keep the sand out. And then I just put 4 or 5 inches of reef sand on top. Worked really well. I never had a nitrate problem. I used snails and a brittle star to keep it stirred up.