Deep Sand in Fresh Water Tanks?

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DeeDeeK

Aquarium Advice Apprentice
Joined
Apr 25, 2009
Messages
14
Location
San Francisco
I have a friend who has been in the hobby for forty years and he uses three at a bare minimum to five inches of this really nice rive sand with smooth, rounded grains that don't pack very tightly. He doesn't have problems with poisons burping up out of the sand. His water quality is always excellent at 0nh3, 0no2, and like 5no3. He plants his aquaria heavily and only uses mechanical filtration with filters rated for half the tank they're hanging from, and does few water changes.

His tanks are clear and beautiful, with very very few sick fish ever.

I'm running a FW tank now with 3" river sand, many plants, and california blackworms, MTS, and a harmless species of planaria roaming around cleaning and oxygenating the sand as they disturb it. Well, the planaria don't disturb much at only 1cm long maximum. I'm chicken and use a 20 or 30 gph filter, for approx. 10gal, full of sintered-glass media and some poly-fil.

My tank is beautiful, clear, and has no ammonia or nitrites at all and about 5-10ppm nitrates. I know I overfeed some (I also overeat, go figure) though I'm trying to resist. It's got a lot of fish in it, too.

I'm going to remove a few pieces of bio media from the filter every few days until I have none in maybe three weeks time. Then I'll see if my friend's magic approach works for me.

He claims nitrates are reduced in the sand, too!

Does anybody have any experience with this approach working for them? My friend just smiles and chuckles when I ask him about how it can work!

Anyone else farting around with deep sand? Adding critters was inspired by marine tanks' living sand. Anyone out there trying the same thing?

I'm really into learning alternate approaches to mainstream fishkeeping. It would be pretty cool to learn of some other people's experience and knowledge in that area.
 
I just recently went to sand (play sand) in my tank. It is about 3" deep or so. Right now I don't have anything roaming around IN the sand, only the normal bottom feeders working on keeping everything clean.

I'd be interested in hearing how this turns out.
 
With the MTS you won't have any aerobic pockets so you won't have to worry about that. Depending on the plants and the bioload you may have to fertilize. I found a sloping sand works best for me I use about 3 inches in the back down to about an 1 1/2 inches in the front. Are you using any topsoil underneath the sand like the Diana Walstad el natural approach?

The mystery leech in your tank are you sure it is harmless? The other leech shouldn't be a problem.

Depending on how many fish you have you might want to consider keeping the filter for oxygen.
 
With the MTS you won't have any aerobic pockets so you won't have to worry about that. Depending on the plants and the bioload you may have to fertilize. I found a sloping sand works best for me I use about 3 inches in the back down to about an 1 1/2 inches in the front. Are you using any topsoil underneath the sand like the Diana Walstad el natural approach?

The mystery leech in your tank are you sure it is harmless? The other leech shouldn't be a problem.

Depending on how many fish you have you might want to consider keeping the filter for oxygen.

Yeah, I am keeping the filter, just minus the biomedia - to see whether this whole loosely packing sand thing works for me the way it seems to for my friend.

oh, and about the person with the play sand, I'm told it packs down too densely for this approach.

Oh, and no, I don't use soil - that's for my next tank exploration. Right now I only have room for a couple of small tanks and one of them is the nursery/quarantine/hospital.
 
mystery leech

The mystery leech came from plants I got from my friend. He's had those little guys for ages and he assures me they just eat detritus, dead stuff, and the like.

I love invertebrates. Especially mollusks and friendly worms (no flukes allowed!)
 
what type of sand is this??? i return home in 2 weeks and will be starting my 55g and I plan on using sand
 
sandy dunkin'

what type of sand is this??? i return home in 2 weeks and will be starting my 55g and I plan on using sand

I'm not sure other than to say it's a river sand and it looks like your basic light sandy brown quartz type sand. The grains a med/large, say from about 0.5 mm to almost 2 mm and they're definitely worn smooth. He poured me a bag but I didn't pay attention. I'm sure he'll tell me.

The basic idea he told me is get chemically neutral, large grained, smooth sand so it can't compact tightly. I bet he buys his at a ceramics supply place or maybe construction materials supply.

I'm thinking about trying some grog, which is a sort of stoneware clay fired and crushed to specific ranges of size. It's rough but that also means more surface area. For now I need to stick with my current project.

I'll find out precisely what sort of sand he uses and get back with that info.
 
liquid plants

I just removed some biomedia from the system when I decided add more floss to the filter. What a spike! But it was quick, all levels below .25 ppm and still dropping (well, I can't measure that small but it stands to reason). Still, it was disturbing to see so many leaves turn into mush! The whole thing just started four days ago.

On the whole, though, all is going well. I've got approximately a scad of fishes and a load of plants and invertebrates in there. My filter has proven inadequate as a source of turbulence to aerate as the amount of hard-to reach mulm increases and as more gunk is getting digested by the sand. So, I've added an airstone and have a valve in the air line so it just sizzles a few bubbles, enough to circulate water up to the surface.

All my black worms stick their tails out of the substrate and my MTS climb the walls up to the surface if the oxygen is low or maybe the CO2 is high. It happened twice and once some of the fish were gasping, though not many. Still, I felt guilty. Aeration cleared up the problem twenty minutes after I had discovered it.

I saw my first planarian worm since I introduced them! Hooray! I thought they didn't take.

Also, my gold tetras and lampeyes and axelrod's rasboras, oh and my endlers (the Just Add Water fish), are all doing mating dances like crazy and the female endlers actually seem interested for once!

All my glass shrimp but one developed a brown patch on their right sides and cloudy white patches and died one after another. The survivor has a few white marks now but seems otherwise healthy. It eats blackworms like crazy.

Anywho, this whole low-filtration deal seems to be working. Gotta watch the bioload as far as oxygen/co2 goes and as far as waste/ammonia/decay.

I buried a very small chunk of fish (from a fish 'n chips shop) at a centimeter from the bottom of the sand, against the glass. I can see the black anaerobic decay gunk and it extends to about an inch from the surface of the substrate, where it has a very clear border. It spreads a few more inches to each side. No gas yet but I'm sure if the sand were turned over, there'd be a lot of toxic chemicals in its depths.

I've decided to keep a paper journal of all that happens and all that I do to the tank. I don't know why but I just really dislike the high-volume filters, tanks with lots of currents I want to discover all I can about keeping fish in simple, small tanks simply. I should note what I come across.
 
So far, so good

It's been a while since I've posted. I thought I'd try posting what's happened so far and see what/if anyone thinks.

So, I measured my sand bed and it's compacted from 3" to 2.5"-2.75"

The dead fish I buried decayed and disappeared but all the mulm (which I never vacuum) seems to have disintegrated and sunk into the sand bed. There is a visible, sharp boundary only 1/2" down where the sandy-blond-brown sand turns to a reduced-iron looking black. The black extends an inch down and then fades over another 1/2" back into the regular sandy-blond-brown. I've used a turkey baster to probe the sand away from the glass and it seems to be the same everywhere.

Some of the plants' roots don't mind it, but the watersprite cannot stay rooted- the roots turn black and disintegrate. I've read this is due to hydrogen sulfide poisoning. The grasses, cabomba, and others seem just fine.

My nitrates are consistently low even with very few changes of water!

I had problems for a while with plants slowly dissolving, shrimps dying slowly, fry with birth defects, and fish flashing all the time. I couldn't find any visual evidence of parasites, infection, or fungus. When I changed water more frequently, the problem got WORSE.

Finally, I suspected Seachem's Neutral Regulator. I paid close attention to how much I was using and realized I was using about triple or quadruple the recommended amount! I siphon two liters at a time into a big juice jar to change water and had been just guestimating the amount to stir in for each jarful I replaced in the tank. Anyhow, I did a huge water change (80%) and carefully measured out the Neutral Regulator this time. After a day, the fish started acting normal. After a week, the surviving plants started putting out new, healthy growth. The next batch of Endler's Livebearers fry was healthy (except for one little guy I call Stubby). The shrimp didn't make it and I've started over again with cherry shrimp. Seachem told me there was no way it was related to their product. Whatever.

Anyone else have experiences with toxic levels of phosphate based pH regulators? Please do share.

I aerate now because all the decay and the extra Endler's (I can hardly give them away fast enough!) need too much oxygen or create too much carbon dioxide. So I supplement with Flourish Excel since airstones tend to drive off all the CO2.

Currently, the fish are vigorous and most of them are doing various mating displays any time I change the water (and most of the rest of the time), the shrimp and Endler's are reproducing, the plants grow visibly from day to day, and I've got little algae. And the tank smells like topsoil. Oh, and the snails seem to multiply and the fish seem to eat enough babies that there aren't too many. And the worms need restocking every so often as the fish have almost all learned how to catch 'em.

If I could, I'd live in there! It seems so happy and busy.

Oh, my substrate bubbles once in a while but nobody seems to get sick and it doesn't smell like sulfur.

Forgive this long post, please. I'm just so into it that I have to share.

My next tank is going to be based very closely on "Ecology of the Planted Tank" by Walstad. I really look forward to it. I'll start a thread on that when I set up the tank.
 
The latest

So, the excess Endlers are gone and feeding is back to normal. The airstone came out fifteen days ago and the only effect is that my plants are now pearling like crazy and growing like mad. Also I have to remove watersprite about weekly to keep up with it.

Ammonia and nitrites are 0. Nitrates hover around 10mg/l. Water changes are very infrequent now so I'm guess there's denitrification going on somewhere.

The black sand which I could see through the glass has faded to a dull blue-grey and the border between it and the blond-brown surface sand has retreated downwards.

Samples I've taken with a turkey baster are full of very very fine particulate matter and lots of worms, all sizes from around 1mm to a couple of inches. The big 'uns are clearly cali. blackworms and I'd swear I'm seeing their young since even the tiny ones swim in a corkscrew manner when touched on one end and flip over when touched on the other. There are very few flatworms, which saddens me. I really like flatworms. Actually I do have a species which is grouped with planaria but lacks a gut and all other planria have a gut. I guess it just absorbs organic compounds through its skin. Hmmmm. velly intellesting.

The newest member of my ecosystem are this tiny, white, hopping mites that live on the surface. I needed a magnifying glass to see that they had more legs and fewer segments than insects. The fish eat 'em when they even notice 'em.

I've got almost no algae except a couple tufts of black beard algae on some dying leafs. Oh, and these tough specks of a rich green algae that's hard to scrape off the glass. At least it grows VERY slowly.

The MTS are reproducing at last. Sadly, the pond snails are outpacing the MTS about four to one.

I introduced a male betta who like to eat young pond snails and any worms he can catch sticking out of the ground. He's like an addict, cruising around all day snapping at worms.

I still haven't vacuumed yet.

The fish are vigorous with a capital vig. And all the female Endlers are preggo again (I know, big whup). Other species are doing cute little courting dances, so I think everyone's happy. They almost thrash when I feed them. Their colors are excellent!

The shrimp are reproducing and the fish are eating baby shrimps.

And me, well I'm sure if I lived in that aquarium and be very happy.
 
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Worms, glorious worms!

I'm so excited! This morning I was staring as usual into the tank and a true planarian popped out! Well, sort of glided out. So I have planaria as well as that strange, gutless, pseudo-planarian.

Now, if I could only figure out exactly what those tiny, hopping, grey-white, mite-like critters are jumping around on the surface of the water and (I think) nibbling at my floating watersprite.

Any suggestions? They're smaller than the finest pen tip I've ever seen, even architectural pens. I can only see a speck and with the largest, two antennae are visible. With a magnifying glass, I can only make out that they have legs, probably more than six though sometimes it looks like they have only four! Their bodies look like they have a slightly smaller head than their second segment. I'm not sure but I think there's only two segments. They can hop at least 3/4 inch in distance, which is scads of times their body lengths. Some are more grey and some more white. I swear they're the smallest living creatures I've ever seen as individuals. Any smaller and I'd either think they were dust or silt.

I'm afraid I may seem off-topic with all the ooo! and ahhh! over critters but the whole point of my DSB is to foster an ecosystem that takes care of much tank maintanance. I think the bugs are probably not helpful nor are they in the DSB, but the flatworms generally hang out in the sand and eat organics and break em' down further.

Actually when I say ecosystem, I don't mean an independent, self-sustaining sort of thing, but a system in which a little filtration and fishfood are variables. My tank is only "balanced" as long as the filter (10gph) is on and disturbing the surface and I feed the fishies every day but not too much. I've just choosen to incorporate way more animals and plants than are in an UGF tank with plastic plants and only fish and/or amphibians. Both are actually "balanced," just we are part of the balance. If my tank goes out of balance, If I don't intervene, I'm sure it will find a new equilibrium once only algae and those pesky little mites survive. Then all it will need is sunlight!

I think my next project, a Walstad style tank, may be a shot at a self-contained ecosystem. I can hardly wait!
 
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This is an extremely interesting post. You've got me wanting to try something like this now. I can't wait to see how it turns out for you.
 
Not to burst your bubble, but those are copepods and amphipods, which would grow in any established tank, regardless of substrate. Especially a planted tank...

I use a pretty deep layer of pool filter sand, but I use my python to clean it with water changes... Left side of the tank one week, right side the next week... I guess this goes against your wanting a layer of anaerobic activity at the bottom, like you would get with a DSB, but that is not my goal... I wanted a somewhat DSB strictly for aesthetics...
 
bubbles to burst

Well, I didn't really think that tiny bugs on the SURFACE of the water were due to a DSB, so don't worry - I appreciate your concern for my bubbles, but no bubbles have been burst. I wasn't aware of copepods or amphipods which live on top of the surface tension, up in the air, and that seem to suck juices out of surface plant leafs but that's a neat idea! I bet you could be right because I sure haven't seen any insects that small before.

I still wonder if they could be mites. Besides jumping around on top of the water, they like to hang out on top of dry watersprite leafs in the air and to climb around on the glass and that seems very mite-like to me, like some sort of semi-aquatic leaf mite. Anyhow, these little guys are under 1 millimeter long.

I'm probably too lazy to figure it out but I definitely enjoy any new, not too destructive, organisms to my tank. Oh, and I consider my DSB to be an aesthetic choice-I find beauty in all the processes happening in my aquarium and enjoy the way it looks.
 
Sorry! Lately I keep glossing over the important info in some posts, I didn't read yours thoroughly! I didn't notice you said "Surface"!

Maybe some type of water-flea? I have seen them in ponds, but not in an aquarium!
 
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