How Freshwater Deep Sand Beds Work

Hey, I just popped in, and was suprised to find this thread still open! My dwarf frogs passed away, one smushed herself under a piece of wood, and the other caught bloat. I miss their singing. I replaced them with some gorgeous rhinohorn gobies, a species which likes a bit of salt, the way mollies do. So I started adding about 2 TBS salt per gallon to my 29 gallon planted DSB. That is a very low amount, not even really enough salt to be considered mild/low brackish, but it mada an amazing difference in my praecox rainbowfish and livebearers. They are VASTLY more colorful, active, and healthy! My plants were hardwater species for the most part, except for one Amazon sword, the only plant having a problem with the salt. So then I brought home an adorable figure 8 puffer named Festus. He ate the gobies. I don't like to think of it.

Of course, before adding salt I had to relocate my breeding colony of 9 habrosus dwarf cories, along with Peaches, my albino balloon ancistrus. I set up a new 10 gallon Walstad tank for them to live in, along with 4 male Endlers and my betta, Spartacus. The substrate consists of a little red clay mixed with potting soil, covered by white pool filter sand to a depth of 3 inches. They are doing great in there, and so are the plants. A dark grey anoxic layer appeared in the sand shortly after setup, to my satisfaction. I haven't tested the parameters in either tank for a couple months, but there are no problems, so I'm happy with them both.

delighted to see this one bob to the surface again (so to speak) as well. I need to reread the whole thing again from the start; when it was running the first time I was a total noob and overwhelmed by the subject. Now maybe I can absorb it this time.

/waves/good to see you again too d'deeK.

Oooh, I'll look forward to your article. The cories haven't resumed breeding since they shifted house, but if they do, I'll try to get a few pics for a post. I took a very lazy approach to breeding them, because though I did wish to to give the eggs at least a chance of living to adulthood, it didn't seem very likely to me, in a community tank. Out of perhaps 30 eggs from 4 spawnings, only three of my Habrosus kittens survived their childhood in the 29 gallon (formerly known as the Boogoodoogada), and are now 2/3 the size of their parents.

I simply perforated a snack-sized ziploc baggie lots of times with a safety pin, and carefully put the eggs in it, then hung it in a spot where the filter output would flow on it gently. I kept it shaded, too, because the eggs are light sensitive. Once the kittens hatched, I let them out of the baggie to fend for themselves in the mulm. Some came back out of the mulm about a month after that, still tiny but behaving just like normal cories do.

I firmly believe that having a soft sand substrate was critical to my ability to keep cories alive at all, let alone have them breed. When my substrate was gravel, all my cories failed to thrive, including Paleatus, Julii, and Anaeus, which are larger and hardier species than these Habrosus dwarf cories, whose Latin name means "delicate". These are much less timid, and far more active than my gravel kept cories. They constantly filter-feed the fine sand rapidly through their gills, a natural behavior that was impossible for the cories I kept on gravel. After observing this, I will never attempt to keep cories without sand again!

I'm all in!

Hi, just read all of this thread & want to thank you for the learning experience :headbang2:

I just did a complet re-set of my 55 gal with #30 Quartz sand, 3" in front sloping to 5" in back. I used to have a DSB in my old reef tank and absolutely loved it. This will be a discus tank. I'm surprised discus enthusiasts haven't caught on to FWDSB considering they are so sensitive to nitrates. Thanks again for the great reading

Just curious how the established DSB systems written of in this thread are doing now that it has been a while since any posting? Anyone?

Wendy

I just started reading through this thread a bit and I believe i accidentally already began my own FWDSB just this past week, quite unintentionally as i didn't realize this thread existed.

What i've got is a 46 Euro with about 1" of regular red/black Fluorite that i left a gap of about 1-2 inches from the walls so kind of like a Fluorite island. On top of that i put all of the pool filter sand substrate from my dismantled (same day) 20L and laid that down covering the Fluorite entirely. On top of that i laid down new, freshly "washed" pool filter sand so it was cleaner in appearance. So i have anywhere from 2-3" of substrate on the tank. Also in the tank (for info purposes) I have one (now tiny by comparison) chunk of mopani driftwood that's been breaking down for well over 2 years, close to 3, which was how long i had the 20L up and running. It was a moderately planted tank, but i ODd my ferts and killed all but my crypts/dwarf sags/java ferns. I have a VERY healthy colony of MTS and a roughly a dozen fish right now.

Since transferring everything this past weekend, i've had a slight ammonia spike. Reading of around .25ppm according to my eyes and the color matching card in my kit. So this is why i am asking. Is it possible that the disturbance of my old substrate caused this spike? I'm still reading through everything, but would the addition of blackworms and planaria aid in the ammonia levels or is it not related? I know the filters will eventually break this down and i am adding more plants as soon as i can afford to.

Any advice for this DSB newb?

I know that this is an older thread, but I just had a few questions about DSBs and I thought it would be better to ask it here than to start a new thread. (Besides, this has been a great read and I'd love to see the tread and discussion grow even more!)

Have any of you kept goldfish in a DSB setup? I really love black moors and would love to set up a large 55 or 75g tank with a few of them sometime. I also find the FWDSB approach very appealing. I'm just not sure the two are compatible.

I note that high-flow filters are normally recommended for goldfish (2-3x what you'd normally use for a tank of the same size), yet low-flow (1/2x what you'd normally use) is the recommendation for a DSB. What's the recommendation for dealing with this?

Also, I've seen a few recommendations that goldfish not be kept in planted tanks since they can be somewhat destructive to the plants. The recommendation seems to be gravel and silk plants. Again, recommendations? If there are enough plants and few enough goldfish, will the growth tend to outstrip the destruction? Or are planted tanks + goldfish pretty much always a bad idea?

The other concern I have is with the interaction between the inverts and the fish. Again, I've seen recommendations that protein intake be limited to no more than 30% of the total diet for goldfish. That's easy enough when their only food source is in the flakes or pellets or what-have-you that you're feeding them, but how do you manage this when they're in a tank filled with tasty inverts? Should I worry about the fish gobbling up all of the blackworms, etc. and getting sick or do they tend to sort of self-regulate when they have a variety of plant- and animal-based foods available?

(This is all still quite a ways off for me, but I enjoy planning out future tanks and I'd like to hear what the consensus is on goldfish + FWDSB.)

Cheers,
- Symbol

Hmmm. I just started looking at FWDSB tanks and accidentally found this thread. I've been wanting to do a similar setup for my Peacock cichlids, but I'm still in the process of learning and relearning everything involved in such a tank. It's something like uncharted territory for me, with all the supposed dogma that "anaerobic is bad" being drilled into me when I first started the hobby. This thread has been a great help!

I think I'll definitely be introducing MTS, and hopefully planaria, but Peacocks won't allow me to do CA blackworms. I'll replace those with Tubifex, and that should do the trick.

I guess the only thing that stops me is that I don't fully understand it all yet, and I want to know exactly what I'm doing before I dive in. I'll read up on it for month or so, then we'll see where I am.

I built one on a whim a few years ago...75G tank, 2/3 Pool filter sand & 1/3 play sand (mixed), about 3.5" deep. I've had some green spot algae on the the glass (not the plants!) which I think is not relevant to it being a FWDSB anyway. Other than that it's been great. I have 2 large sponge filters plus an HOB on the end of the tank. Since the sand was dead and inert to start with, it took awhile to establish but is now doing well.

Anoxia said:

They constantly filter-feed the fine sand rapidly through their gills

Click to expand...

My loaches do that, as well.