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FAQs on Freshwater Substrates 2

Related Articles: Freshwater Substrates, Nice bottoms; Choosing the right substrate for your aquarium by Neale Monks, Freshwater Deep Sand Beds Work by Deirdre Kylie, Setting up a Freshwater Aquarium, Tips for Beginners,

Related FAQs: Freshwater Substrates 1,
FAQs on: FW Substrate Selection, FW Substrate Physical Properties, FW Substrate Chemical Properties, FW Substrate Amounts & Placement, FW Substrate Changing, Moving, Adding To, FW Substrate Cleaning, FW Substrate Issues, FW DSBs,

Substrate for my fresh Water refugium    1/10/17
The
<The? Is there previous correspondence?>
substrate is made of organic potting mix (no fertilizers, at least as written on a bag)
<I'd be testing... by soaking, perhaps boiling a teaspoon or two in some water... testing the liquid>
- about 2 inch thick,
<?! This is a BUNCH of material; too likely to "float out"... a mess. I'd be mixing the soil with fine gravel...>

.5 inch of fine gravel op top of soil and 1-1.5 inch of smooth white sand (not aragonite) Do you have a tip,
<A tip? I'd be doing more searching here... on WWM, the Krib... Diana Walstad's works; maybe Takashi Amano. What you have done here so far?... Not viable>

I set up a fresh water refugium for plants and fry. I bought a bag of organic potting mix from Menards and put it in the middle chamber and it just floats.
<Oh yes; assuredly>
Above is from a blog I got from your site and read the same from others.
<Can't tell what is lifted without quotation marks, notes... Maybe have someone else read what you send out ahead of time to assure it makes sense.
Bob Fenner> 

Clown Pleco substrate safety question       8/28/16
Good evening,
<Jennifer,>
I've found myself in a dilemma after following the advice of a local fish supply store (with a good reputation) and purchasing a Clown Pleco for my ex-Betta tank.
<Do double check what species you actually got. The "true" Clown Plec is a Panaque species called Panaque maccus (sometimes called Panaqolus maccus).
It's a herbivore more than anything else. It isn't fussy about the substrate because it prefers to spend time on rocks and especially bogwood.
However, a lot of aquarists (and some older books) use this Clown Plec name for a Peckoltia species, Peckoltia vittata. Like all Peckoltia, this species is a micro carnivore that roots about for worms and such. This species will be more upset by the substrate if it can't dig easily.
PlanetCatfish.com has nice photos of the two species if you need help telling them apart.>
My Betta had passed away after 4 years and I hated to get rid of the mature 5 gal tank, but wasn't ready for another Betta so soon. The store convinced me Clown Plecos stayed small and would do fine in a small tank. Ha! I now
know this size tank is inadequate for him for many reasons, so I want to move him out of there before it stunts his growth.
<Understood. Both the catfish mentioned are relatively small, around 8 cm/3 inches or so in length. The Panaque species is marginally bigger perhaps, but there's not a lot in it. Anything upwards of 20 gallons is fine, and you could probably get away with a 15-gallon tank at a pinch.>
The problem is I only have one other tank option and I'm not sure the substrate will be ok for him. I've read some conflicting information online. The current 5 gal tank has a nice sandy bottom (smooth sand, not the sharp kind I've read about) with driftwood and he really seems to like it.
<Panaque species are wood-eaters, and will spend all their time, if they can, on bogwood, rasping away. They also consume vegetables like courgette/zucchini, as well as algae wafers and the odd bit of something meaty.>
My other tank is a 75 gal planted tank with large pieces of driftwood with lots of places to hide from the 2 goldfish occupants. But the substrate is Seachem's Fluorite gravel.
<Not a major problem for Panaque maccus. As noted, this catfish prefers to stay on solid surfaces, especially bogwood, and rarely comes down onto the substrate except to eat things like algae wafers put out for it.>
It doesn't seem sharp to the touch, but it's not really as smooth as other traditional gravels, so I'm worried it isn't a safe fit for the Pleco. I hope I'm wrong because otherwise I think he'd really love the tank. I'd appreciate any advice you can offer. Thank you in advance for your time!
Sincerely,
Jennifer
<Hope this helps, Neale.>
Re: Clown Pleco substrate safety question       9/5/16

Good evening, Neale.
<Jennifer,>
Thank you very much for the reply. It has helped ease my worries! After researching the two species you mentioned on PlanetCatfish.com, I found I do indeed have the true Panaque maccus Clown Pleco. Although I don't see my
little guy much during the day, when I do glimpse him, he's always rasping on the driftwood. And he leaves numerous piles of "wood dust" all over the sandy bottom. It still amazes me how much debris such a tiny thing can create so quickly!
<For the last 20 years I've looked after one of his bigger relatives, Panaque nigrolineatus, a truly wonderful fish. But this thing poops like it's an Olympic Sport! Absolutely standard for the genus, as you've seen, but since it's mostly wood chippings, the effect on water quality is nil.
Probably a useful soil improver too, but can be unsightly, and easily siphoned out, or "spot cleaned" with a turkey baster. Do have a read here:
http://www.wetwebmedia.com/fwsubwebindex/panaqueart.htm
Plenty of info on this really interesting group of catfishes.>
We are undergoing a renovation project (hence the reason for my delayed reply), but as soon as that is over, I will be moving him to the 75 gal tank where he will hopefully enjoy many happy years.
<Should do. Panaque are notoriously sensitive the first few weeks, and getting them feeding well is crucial. But once settled they are VERY hardy and long-lived.>
Thank you, again!
Sincerely, Jennifer
<Most welcome! Neale.>

Re: Questions about second hand tank.  Now FW substrates   6/16/12
Thank you so much for your <sic> advise.
<Welcome.>
I came to you guys a couple years back (it was you Neale who gave be Betta tips), and it helped my fish live for 2 years (never was able to diagnose what took him under, he showed no signs of age-color-loss, but his body was curling near the end of his life).  One thing I wanted to know a little more about was use of sand as substrate- scouring the net yield mixed results, and I am curious about pros and cons.
<Do read: http://www.wetwebmedia.com/fwsubwebindex/nicebottoms.htm
In short, the positive aspects of sand are that burrowing and digging fish like better, it's more realistic for many biotopes (e.g., the Amazon), and to some degree it's less likely to get dirty than gravel because muck can't sink downwards into the sand. On the negative side, because the muck doesn't sink into it like it does with gravel, any dirt is more obvious, so you need good filtration and regular tank cleans to keep the aquarium looking smart. Sand can also be pushed into filter inlets if the inlets are too low down (or your fish kick the sand up into the water column).
Finally, sand tends to be lighter in colour than gravel, and in the absence of overhead shade, such as that provided by plants, your fish may appear more washed out in colour than usual.>
Again, thank you for helping me out. If you guys have a Facebook page, I will be sure to give it a like and spread the word.
<I believe we do.>
Its great to get solid answers from real folks online when the net is full of false info and scam artists. You guys are true pros- keep up the good work!
Steve
<Thanks for the kind words. Cheers, Neale.>

Black Mollies and "Pea gravel" 12/4/10
Hello:
<Hello Judy.>
I was wondering if it is ok to keep no more than three female black mollies in a 20 gallon long with no other fish???
<Certainly doable. Assuming these are Shortfin Mollies, they should be okay, especially if you added a wee bit of salt to take the edge off any nitrate toxicity, nitrate, almost as much as soft water, being the thing
that stresses Mollies when kept in small aquaria. Aim for 2-3 grammes/litre.>
Also I have a question about aquarium gravel. The other day we got a 20 pound bag of "pea gravel" for the garden at the hardware store. I was going to use some it for aquarium gravel, but there are all these little sand particles all through it, and I was thinking that may not be good for an undergravel filter. Maybe I should just buy straight aquarium gravel from the fish store.
<Garden gravel is usually fine, and what I use all the time. Provided it is sold as "pond safe", it should be safe.>
I can rinse of some of the sand, but it is impossible to get it all. Would this affect the undergravel filter?? Thank you
<A little sand won't do any harm, but obviously the more crud underneath the undergravel filter plate, the less water will flow through it, so yes, you need to rinse the gravel as best you can.>
Judy
<Cheers, Neale.>

Re: More re: Removing silicone (RMF, anything to add?), now substrates, learning to use WWM 9/29/10
Oh, had another question I meant to ask. I'm intrigued about this sand idea of yours. I think it would look so much nicer than the painted rocks. What type of sand do I get? Play sand? Or do I need some sort of special pre-cleaned sand or something?
Amanda
<... Mmm, please read here:
http://www.wetwebmedia.com/FWSubWebIndex/fwsubstrates.htm
and the linked files above. BobF>
Re: More re: Removing silicone... and sand again
Thanks, Neale! I got impatient and did the test fill last night. It had been 24 hours. Used the GE 1* W&D. SUCCESS!!!! :D My very first repair job and no leaks!!
<Well done!>
Granted this has to have been a much easier repair than an all glass aquarium, and I also have the benefit of water pressure pushing the joint tighter instead of threatening to pop the seam.
<Indeed.>
I've been looking at sand, and I think play sand will be the best I can afford as I'll need over 50lbs of it.
<Many people have indeed used play sand, pool filter sand, and various other types of sand.>
I see it mentioned as safe on many sites, do you concur? It also looks like Natalie (if memory serves) uses it regularly?
Amanda
<The bottom line is that is if it is [a] non-calcareous and [b] smooth rather than sharp (technical terms that mean precisely what they sound like) then any sand should be fine in an aquarium. You can test the lime-content of sand easily enough yourself by adding some vinegar and seeing if the sand fizzes; if it does, then it's not non-calcareous and will raise the carbonate hardness and pH over time. That may or may not be a deal breaker depending on the types of fish you're keeping. As for sharpness, if it feels smooth and silky rather than abrasive, then it's probably smooth sand, and therefore unlikely to scratch burrowing or bottom-dwelling fish. I have to admit that I resolutely stick to recommending only horticultural smooth silica sand precisely because you can guarantee it'll be lime-free and non-abrasive. Other types of sand may or may not be safe, but there's no copper-bottomed guarantee I can offer you via e-mail. For what it's worth, a 25 kilo (~50 lb) bag of smooth silver sand from my local garden centre costs about £4, or about $6. Whatever sand you plan to use, be sure to clean it thoroughly before use. Cheers, Neale.>
Re: More re: Removing silicone... chatting
Oh, wow! Thanks for the tip on the silica sand and the lightning fast response!
<No problem.>
There is a nursery just 2 miles from my house. I'll check it out.
<Cool.>
Right now I have 2 red flame Gourami, 2 zebra Danios, 2 mollies and a sunburst wag platy. I plan to add red wag platies (wow is their color amazing!) over time once the bigger tank has cycled properly. I'll be using my Penguin Mini as well as my new Penguin 200 in the big one for a while to assist in bacteria growth before moving the mini back to the smaller tank and then getting some GloFish for that tank. No telling where I'll go from there. I'm so excited to get this new one going! Who'd have ever thought my
son coming home from daddy's with a 12" goldfish would kick off such a passion. :D I got a whopping 3 hour notice on that massive goldfish.
Fortunately I was able to convince the junior homo sapiens that "Nemo" would be much happier back in his pond.
<Quite so. Goldfish generally make quite poor aquarium fish unless given really big tanks. Do review the needs of these tropical fish of yours.
Mollies tend to be finicky fish if kept in plain freshwater, though hard, basic water helps a good deal. Dwarf Gouramis are ridden with viruses and bacterial infections, so I tend to recommend people avoid them in favour of Banded and Thick-Lipped Gouramis (Colisa fasciata and Colisa labiosa) which are both much hardier and long-lived than Colisa lalia. If Danios are your thing, I'd nudge you towards Danios, Platies, Peppered or Bronze Corydoras, and perhaps something like Flag Acara for the midwater: all of these are healthiest if kept slightly on the cool side, 22-24 C/72-75 F being ideal.>
Amanda
<Cheers, Neale.>
Re: More re: Removing silicone, more chatting... bb-referral please
Had to look up the Flag Acara and Corys,
<In fact almost all Corydoras will work, the exceptions being Corydoras sterbai which prefers warmer water. Acaras are cichlids that tend to prefer slightly cooler conditions than the average tropical fish, with the Flag Acara and Keyhole Acara being very peaceful community fish. The Port Acara isn't as pretty, but extremely hardy, even bullet-proof, and becomes very tame.>
but I think I could be happy with that assortment.
<We aim to please.>
Will definitely keep that in mind as I add fish. Thanks yet again! :D Will be going for platies and Danios first. ;)
<Good move. Do watch the Danios though: they can be bullies, and will nip smaller species like White Cloud Mountain Minnows. Zebras and GloFish are the same thing species-wise, so they get along okay. Pearl Danios are a good choice too. But if you hunt about, there are some cracking species out there, for example Leopard Danios, Glowlight Danios, Ocelot Danios and Queen Danios.>
Amanda
<Cheers, Neale.>
Re Silica Sand, was Removing silicone 01/10/10

I tried one of the local nurseries today and the guy acted like he didn't know what I was talking about. The one closest to my home closes before I get home from work. Will try them Saturday.
<When searching in Google I did find that the names "silver sand" and "silica sand" do seem to be more in the UK than the US; in the US, it seems terms like "quartz sand" are used more often, quartz and silica being the same thing. Essentially you want a lime-free sand from the garden centre, which they should sell because it's a widely used as an additive to soil, particularly houseplants where it improves drainage. There are two grades, here in England at least called "sharp" and "smooth" depending on the smoothness of the grains. For aquarium uses, you want smooth sand.>
Some friends of the family own a pool supply business. I see some people use pool filter sand, what is your opinion on it? With the walls of the tank being so dark I wonder if a white substrate might help lighten the tank and make the fish more visible. What are your thoughts?
Amanda
<Pool filter sand is widely used. Provided it's quartz or silica sand, and therefore lime-free, and also feels smooth rather than sharp, it should be fine. As for the colour of sand, that's argued over. Bright substrates tend to cause some fish to lighten their colours. You'll notice this with cichlids and tetras especially; not so much with fish like Platies that have been bred to have colours they can't change. Anyway, if the tank is
densely planted, those fish that like shady areas, such as cichlids, will stay close to the plants so all will be well. But there's no getting away from the fact fish colours tend to look more dramatic against a dark
substrate, whether plain gravel or black sand. The problems with black sand come from its much higher cost and, in some cases, its abrasive texture which means it can't be used with fish that live on the substrate, such as catfish and loaches. Manufacturers like Carib Sea state as much on their web sites, though some aquarists choose to ignore this, and then wonder why their catfish has no barbels. Cheers, Neale.>
Re: Silica Sand, was Removing silicone 01/10/10

I've called nurseries, landscapers, hardware stores, DIY stores, no one has silica sand, regardless of what you call it. *sigh* I think what I'm going to do is get the pool filter sand ($7 for 50#)
<OK.>
and then get a couple small bags of sand from Petco or Bob's Tropicals to add over the top if I can't find it cheaper over the next couple of weeks.
<Why? It'll all get mixed up anyway. Sand doesn't sit in nice layers!>
A 5lb bag of CaribSea sand at Petco was $15. Absolutely outrageous!!
<Indeed.>
But, I really want to get this tank going! I'm getting very impatient. LOL
Amanda
<Do read our articles about sandy substrates.
http://www.wetwebmedia.com/fwsubwebindex/nicebottoms.htm
http://www.wetwebmedia.com/ca/volume_7/volume_7_1/dsb.html
Cheers, Neale.>
Re: Silica Sand, was Removing silicone 10/2/10

<and then get a couple small bags of sand from Petco or Bob's Tropicals to add over the top if I can't find it cheaper over the next couple of weeks.>
<<Why? It'll all get mixed up anyway. Sand doesn't sit in nice layers!>>
Just so it won't be stark blinding white, no other reason at all. ;) I don't care how it winds up settling, in fact, I think it mixing well would probably look nice. Especially if the current in the tank made it wind up looking kind of marbled like you often see in stream beds. :D
Amanda
<Hmm'¦ okay. Cheers, Neale.>
RE: Silica Sand, was Removing silicone
I FOUND SOME!!! I called a sandblasting company and asked who their supplier was and was referred to Williams Equipment. They have 40/95 grade.
$9.75 for 100lbs. Is that grade going to be ok?
Amanda
<Honestly Amanda, I don't know. I've never used sandblasting sand. But if it's smooth, lime-free silica/quartz sand, it should be fine. Do bear in mind sand sold for sandblasting is unlikely to be washed. So you'll need to do a lot of cleaning to make it suitable for the aquarium. Otherwise you'll find the water goes cloudy and there's floating debris and silt everywhere.
Cheers, Neale.>
Re: Silica Sand, was Removing silicone
Will be adding more plants as time goes on, including the ones in their present tank. I am loving it so far!!
Amanda
<Looks nice. Try adding some hollow ornaments for cichlids and catfish to
hide in. Some species will hide in the sand -- for example whiptails -- and
that's very cool to see. But others prefer more solid caves. Halved
coconuts with "mouse holes" cut in the edges and then some Java moss on top
make excellent caves for small cichlids. And before Bob blows a gasket, do
remember we have a very friendly forum where you can share photos and get
comments from other fishkeepers. Much as I like chatting about fish, Bob is
keen to keep the Daily FAQs focused on emergencies, and the more sociable
stuff over on the forum.
http://bb.wetwebmedia.com/
Have fun! Cheers, Neale.> <<Thank goodness. B>>

New substrate
Changing Substrate 5/1/10

Greetings, I currently have a 55 gal tank set up and cycled. I bought it used and it already have gravel in the bottom, I have not had any problems with this tank so far. Currently it houses 8 Pseudotropheus demasoni. The substrate is a similar color as the fish and I would like to change it.
What I was thinking was using fine white sand along with a white crushed coral to help it from getting too compact. The demasoni are happy as can be (without directly talking to them) and I'm afraid that with the stress of getting moved out of their tank, having to do a larger than usual water change and adding the coral is going to disrupt them too much and change the pH. What are your thoughts on this? I know I should be testing the pH already but I'm shying away from testing because I'm too much a perfectionist and would do more harm then good trying to get the water just right. Regards, Paul
<Take a sample of your tank water and a sample of your tap water to your local fish store and have the pH checked. If your pH is already greater than 7.0 then there probably won't be a problem changing the substrate.
Watch for ammonia and nitrites spikes since you essentially will have a "new tank". I would recommend that you don't clean the filters for awhile until the bacteria get established in the new substrate.-Chuck>

Changing Substrate in an Existing Tank 5/3/10
It might be interesting to have a chime in on doing a substrate change without moving the fish. I did this gradually over a few days using play sand.
< Play sand may or may not be a crushed aggregate. If it is crushed then the individual particles with be angular and abrasive to bottom dwelling fish. sometimes this will cause trauma to the mouth parts of bottom feeders and create infections around the mouth and gills.>
This got very cloudy but the fish seemed OK with it.
< I would recommend that all substrates be washed prior to placement in an aquarium.>
May not have the cloud issue with something besides play sand. For me it wasn't dirty sand, the Quikrete stuff that I used is prewashed but still is quite fine and likes to float. I have since added some better sand with a darker color to bring out the spots in my Cory cats.
I found that if you go slow the fish will give you plenty of room without freaking out. I also used two methods to lessen the disturbance. First, and foremost the sand needs to be wet before entering the tank. Large scoops seemed to be fine but the trick is not having the sand float out of the scoop before reaching bottom.
I also used panty hose where I filled it up and sank it to the bottom of the tank and sifted out but grew impatient with that. And to get the gravel out I used a sink strainer so I could lift the substrate without taking any of the water.
Also, adding anything course, make sure not to rain it on the fish.
Now, what I did could have been totally inappropriate but if not perhaps feedback on whether this method is OK if you go slow and gentle on the change.
< Your suggestions on doing the physical act of actually changing the substrate are fine.>
What is the tradeoffs between this and doing transfer and full water change?
<The Ps demasoni are not touchy fish. So it becomes a matter of logistics and time. I would have done it all at once since these fish are fairly
tough. If I was working with a more delicate species, then I probably would have changes the substrate about 1/4 at a time and gauged the reaction from the fish to make sue they are not too stressed.>
Or perhaps a hybrid method of doing a 50% water change which is what I did using the old substrate and water in a holding tank during the change (which I did not).
Come to think of it, I think I'd do the 50% with transplant if I were to do it again. On the other hand, with 19 fish to chase and scoop perhaps not.
That has got to be a lot of stress but I'm not sure which is more stressful.
Finally, if you take water samples to a store GET THE NUMBER and not just "it's fine" as a result. Home testing and this website have been the best combo over trusting anyone with my fishes health.thx
< Good advice, thanks for the comments.-Chuck>

Questions on Freshwater Deep Sand Beds 3/17/10
Hello!
<Hi there>
I must commend all of you for keeping up such a wonderful and helpful site.
I greatly enjoyed the most recent Conscientious Aquarist Magazine. Ever since reading one of the FAQ a while ago where an upcoming article on freshwater deep sand beds was mentioned, I've been eagerly awaiting its release! What a helpful article! (I will certainly start leaving roots behind when I move/rescape plants.)
Of course, like all good information, it leads to so many more questions!
My system is a well-established 135gal densely planted discus & community tank running on a 75gal sump, with pressurized CO2, high light, and substrate heating cables. I have a couple questions about using a DSB on this system. The substrate, currently, is about .75' of mineralized soil capped with about one cm of Oil Dry (identical to Fluorite, but more economical) and 1-3' of pool filter sand on top, depending on location in the tank. Do you think I could turn this substrate into a DSB (rather, would it be worth it, when the system works well as is?).
<I think that all sand beds function in part as DSBs, with deeper ones, of smaller/finer, rounder, more chemically propitious ones operating better>
While I don't think that the soil would cause a problem if I were to start using the substrate as a DSB, would the Oil Dry?
<I don't think it would>
It has 'large' pebbles, just like Fluorite. Also, substrate heating cables allegedly move oxygen through the substrate; would these cables, by doing their job, just make developing a DSB impossible?
<Some partial (not anoxia, by hypoxia) oxygen through induced heat/convection (along with Brownian Motion et al.) is valuable>
The only other 'real' sand disturbers in the tank are the sterbai Corys, Malaysian Trumpet Snails and their Assassin counterparts (to be fair, I have to grow the MTS in the sump and periodically move them, as the Assassin gang wipes them out faster than I can add them).
<Both neat animals... that do a bunch of burrowing as you know>
I already had Blackworms on the way, intended for use as discus treats. If I add them to the tank on the substrate, they will be found and eaten quickly -- can these be buried without killing them?
<They will/do find their way into some depth, low oxygen settings>
Or would I be better to add them to the tank at night, in the thickest bits of plants? What will the bioload of the worms do to the balance in my tank?
<I would not add these on purpose myself. These worms live in conditions that you really don't want to replicate for your other livestock. If some live, so be it>
The tank is densely planted now, such that even with 900+ gph turnover from the sump plus a *Koralia 2 powerhead, mulm still settles on the substrate (beneath the plants). If I understand the article correctly, I should leave this mulm? It seems to sit on the substrate rather than move into it.*
<Some is okay... depending on the type of livestock you keep... I'd siphon some out for looks periodically, along with water change-outs>
My other alternative would be to add a DSB to the sump rather than the tank.
<Yes>
There *is* currently a 'freshwater 'fuge' area in the sump (I can hear the salties chuckling from here!) that I could add sand to. Would this perhaps work better than in the main tank?
<I like both sites for many types of FW set-ups... the remoted/sump/refugium is better for maintenance, manipulation obviously>
Or in addition to a DSB in the main tank?
<Up to you, or both>
Is there any benefit to making the sand bed deeper than the three inches laid out in Deirdre Kylie's article (3' seems shallow as is?)? (If so, by how much?)
<Mmm, yes... 4-6 inches isn't too much, again, depending on what you're growing, wanting to do... and of course the trade-offs you're making with losing the equivalent water volume>
Thank you so much for all you do, especially putting up with merciless picky questions like these!
Tianna
<The "devil" and heaven are "in the details". Keep that good mind of yours going Tianna... we/the world need it and you. Bob Fenner>
Questions on Freshwater Deep Sand Beds, Neale's go 3/17/10
Hello!
<Hello,>
I must commend all of you for keeping up such a wonderful and helpful site. I greatly enjoyed the most recent Conscientious Aquarist Magazine. Ever since reading one of the FAQ a while ago where an upcoming article on freshwater deep sand beds was mentioned, I've been eagerly awaiting its release! What a helpful article! (I will certainly start leaving roots behind when I move/rescape plants.)
<It is an interesting piece.>
Of course, like all good information, it leads to so many more questions!
<Oh?>
My system is a well-established 135gal densely planted discus & community tank running on a 75gal sump, with pressurized CO2, high light, and substrate heating cables. I have a couple questions about using a DSB on this system. The substrate, currently, is about .75' of mineralized soil capped with about one cm of Oil Dry (identical to Fluorite, but more economical) and 1-3' of pool filter sand on top, depending on location in the tank. Do you think I could turn this substrate into a DSB (rather, would it be worth it, when the system works well as is?).
<There is a minimum depth referenced in that article. I can't remember off-hand the number, but if the substrate you have is LESS than that depth, no, it won't work as a DSB. Particle size will make a difference though; the finer the substrate, the better it works as a DSB. To a degree, you have to experiment a bit if you're going to depart from the recipe. For what it's worth, in my tanks I observe DSB-like activity once the substrate depth is around 10 cm or so (about 4 inches).>
While I don't think that the soil would cause a problem if I were to start using the substrate as a DSB, would the Oil Dry?
<I don't know. Never even heard of "Oil Dry".
It has 'large' pebbles, just like Fluorite.
<Pebbles are bad. You want a uniformly fine substrate. If you think about it, if a bed of sand works as a DSB, but a chunk of concrete of the same size doesn't, then anything less like sand and more like concrete will be less effective.>
Also, substrate heating cables allegedly move oxygen through the substrate; would these cables, by doing their job, just make developing a DSB impossible?
<Again, I don't know, but I doubt the convection currents created by a substrate heater would make a huge difference either way.>
The only other 'real' sand disturbers in the tank are the sterbai Corys, Malaysian Trumpet Snails and their Assassin counterparts (to be fair, I have to grow the MTS in the sump and periodically move them, as the Assassin gang wipes them out faster than I can add them).
<Yes! aren't they fabulous little predators!>
I already had Blackworms on the way, intended for use as discus treats. If I add them to the tank on the substrate, they will be found and eaten quickly -- can these be buried without killing them?
<Possibly, but I wouldn't bank on it.>
Or would I be better to add them to the tank at night, in the thickest bits of plants?
<Could you use a yoghurt pot or something similar to "seal off" a portion of the substrate, put the worms underneath, and leave in place like that for the night? That should keep out the catfish.>
What will the bioload of the worms do to the balance in my tank?
<Hopefully not much overall. While they will add to the ammonia produce and will consume oxygen, by improving the DSB, they should improve water quality.>
The tank is densely planted now, such that even with 900+ gph turnover from the sump plus a *Koralia 2 powerhead, mulm still settles on the substrate (beneath the plants). If I understand the article correctly, I should leave this mulm? It seems to sit on the substrate rather than move into it.*
<Will do so initially, but like leaf litter on the soil, the bottom layers are slowly decaying into the substrate.>
My other alternative would be to add a DSB to the sump rather than the tank.
There *is* currently a 'freshwater 'fuge' area in the sump (I can hear the salties chuckling from here!) that I could add sand to. Would this perhaps work better than in the main tank?
<The bigger the DSB, the better, but a small one in a sump is certainly worthwhile, and much done in marine fishkeeping.>
Or in addition to a DSB in the main tank? Is there any benefit to making the sand bed deeper than the three inches laid out in Deirdre Kylie's article (3' seems shallow as is?)? (If so, by how much?)
<Up to a point, yes, a deeper DSB is good, but there's a balance between creating the DSB and wasting water capacity by filling the tank with sand. By all means add an inch or two and see how things work out, but I wouldn't go crazy.>
Thank you so much for all you do, especially putting up with merciless picky questions like these!
<Happy to help.>
Tianna
<Cheers, Neale.>
Re: Questions on Freshwater Deep Sand Beds -- 03/18/10

I am spoiled! Two great answers for one question! Thank you so much!
<Welcome>
A follow up question, if I may? I think I will start with a DSB in the sump, as should I not like it/something go wrong, it is much easier to remove without stressing the fish.
<Agreed>
If I like that, I will add more sand to the display. Would I count the mineralized soil towards a ~4" depth for the DSB, or just the sand?
<All counts>
It would seem that total depth would make sense, except for the concrete analogy - I am sure that over time the soil has compacted very much.
<And even "disappeared">
For interest's sake (and for all of the economical planties out there), Oil Dry is a product used in automotive and manufacturing industries, among others, to clean up oil. It (or at least some of it) is a pure clay product that is apparently "food grade" (although I can't fathom how/why you'd have food grade clay...and I probably don't want to know!). Because of the nature of the product, it is extremely inexpensive and can sometimes even be found free.
<http://www.oildri.com/>
Neale, I did try your great (and so simple!) re-purposed container idea - which did let the Blackworms into the substrate - but since the worms rest with their heads (tails?) skyward, the Corys simply slurped them from the
sand like spaghetti. Based on Bob's recommendations, I won't try adding them again.
<Will share w/ him>
Thank you again for everything that you do for the hobby! (And thanks Bob for that great lecture at CAOAC last year!
<Ahh! A very nice time out in Ontario, Canada>
This tank was the lonely "yes" in a room primarily full of freshwater hobbyists when you asked who actually ran a sump.)
Thanks,
Tianna
<Thank you, BobF>

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