Substrate choices

[Magnum Man]

When I was into tanks 20 years ago, everything was under gravel filters… and standard aquarium gravel was the normal… today a lot of people are using sand… when I restarted my tanks, I kind of experimented both with and without under gravel filter plates… and while my next tank to fill, will be sand, my favorite for several reasons right now, is river rock about 1 inch in diameter… right now I’m wishing more of my tanks had just river rock, varying colors between tanks for variety…. I still have 2 - 30 gallon long tanks to set up, from my old built in tanks, those and any new ones will definitely be river rock… plants that don’t do well being buried, thrive with a piece of lead free solder, and dropped into the river rock, my Cory’s thrive in the river rock, even my coolie loaches love the river rock, swimming between the gaps of the larger stones…

Anyone else do a tank with just river rocks???

 

[Wills]

Its quite hard to say what the most natural approach is in some respects - I always thought it would be impossible to see a river bed that is pure fine-grain sand but I've seen plenty of footage where that is the case but a lot of it is also as you have described with river rocks - indeed a lot of Central America looks exactly like this.

Even in our bigger tanks it is impossible to cover all of the areas of habitat our fish inhabit - we can offer on average a 1.2m long tank upto 60cm deep but most of the fish we keep are from habitats where they could roam many multiples where they might span pure sand, large rocky base, small pebbles, dense leaf litter.

I like to keep fish on a mainly sand substrate but with some larger rocks and where possible something to grade in, I think sand is the easiest substrate to keep on top of and the gentlest for the fish to live with but then the graded substrates make it look more natural to me as a viewer.

Wills

 

[Back in the fold]

There’s still a place for gravel . There is also still a place for under gravel filter plates . Sand is appropriate to certain environments and fish gravel to others . I like both . A guy could have an aquarium full of Zebra Danios with gravel and it could look much like a trout stream . Sand wouldn’t be quite the same .

 

[GaryE]

It really depends. I have some fish here where being natural to the biotope I caught them in would mean quicksand as a substrate. I can get a brown pool filter sand/gravel that doesn't bother Corydoras, and what I usually do is mix it with playground sand. It's my favourite, and worth a drive to the pool supply store.

Before my move, I let some tanks dry out and just left the substrate in them dry for the trip. In some tanks, I have the same gravel and sand I had in them 15 years ago.

I wouldn't use 1 inch river gravel as it's a decay trap. I do sometimes scatter river rock onto sand, or pick up rounded beach pebbles and do the same. They work into the sand in time, and provide cover for fry. I also use a lot of larger rocks scattered to look random.

One person's gravel could be another's sand.

 

[AdoraBelle Dearheart]

Its quite hard to say what the most natural approach is in some respects - I always thought it would be impossible to see a river bed that is pure fine-grain sand but I've seen plenty of footage where that is the case but a lot of it is also as you have described with river rocks - indeed a lot of Central America looks exactly like this.

Even in our bigger tanks it is impossible to cover all of the areas of habitat our fish inhabit - we can offer on average a 1.2m long tank upto 60cm deep but most of the fish we keep are from habitats where they could roam many multiples where they might span pure sand, large rocky base, small pebbles, dense leaf litter.

I like to keep fish on a mainly sand substrate but with some larger rocks and where possible something to grade in, I think sand is the easiest substrate to keep on top of and the gentlest for the fish to live with but then the graded substrates make it look more natural to me as a viewer.

Wills

I couldn't agree more! I've been questioning and considering substrates since I joined the forum, especially since getting cories. And that we have a hard time replicating how animals would live in the wild, our chances of re-creating that natural environment as much as possible in a glass box.

I have a tank that's half sand, half gravel, and I think there are benefits and downsides to both. Love the tiered, mixed substrate biotopes and aquascapes, and want to recreate some of them in my own tanks, and need to learn how! Have plans to set up new tanks, with different substrate disturbers, so have a lot of substrate considerations for the different species. I want a large tank suitable for a group of botiid loaches. Strong flow, few plants in the substrate, but some rhizome and floating plants, river rocks and stones, a height difference in the substrate, and possibly, grain size changes and a sandy area too.

Another tank with planted substrate, lots of different plants and densely planted, and no substrate disturbers.

Another for my cory gang and plecs. So a large fine sand area, but I also want a higher area with different grain sizes, where some mulm can form, oak and almond leaves can break down, and thicker, deeper rooted plants can grow. I'm convinced that the micro critters that are encouraged and can populate the tank from the mulm and leaves breaking down - are what my pygmy cory fry live and thrive on, so can raise themselves in the tank. Mulm and possibly some capped planted substrate, will help the deeper rooted plants that cories can't uproot, and will provide good cover for cories to hide away in when they want, and sand for them to filter feed when they come out into the open.

So I want to learn about a range of substrates for different fishes' needs. (@Seisage your lesson worked here! )

this incredibly informative post I'm also now newly concerned about pockets of anaerobic bacteria in sand only substrate... She followed up with a photo and more info on the next page of that thread. Since she's a marine scientist, I trust what she's saying, and wondering if we're not taking this seriously enough as a hobby, and whether it'll crop up as an issue more and more often as sand has become so much more popular gravel, and does have it's benefits too.

 

[TwoTankAmin]

I have done tanks bare bottom, with sand, with small sized gravel and with large sized gravel- aka river gravel. I have larger river rounds in tanks as well on top of the substrate. But I have never done an all small river round bottom. The one thing I would worry about this bottom layout would be an accumulation of gunk in spots around the bottom which might be hard to clean or even to locate at times. I think some use of downward facing powerheads (not with big flow) might keep the pre-gunk stirred up well enough so that the filters could grab it out of the water before it can accumulate.

A number of my planted tanks have a thin layer of sand but all of the plants are attached to rocks and/or wood and/or also may be planted in substrate in clay pots.

I have bred a lot of bn plecos and a few of the B&W Hypancistrus. I have done this in bare bottom, sand bottom and small gravel bottom tanks. The bn plecos are normally in tanks with plants while the Hypans are in unplanted tanks.

 

[Magnum Man]

The one tank I have with no under gravel filter plate, & between 1 to almost 3" "river rounds" ... I still do vacuum the rocks ( not too much, as I have Coolie loaches that live in / under the rocks... that tank has a big population of pond snails, as well as assassin snails, that work the gaps between the rocks with the coolies, & a pretty high fish density as well... & lots of Java Fern on the bottom... in about a year, it's all been good...

the bacteria pockets is something I don't like about deeper sand... in the one I'm setting up next ( a sand bottom ), I'm only going about an inch deep of a little coarser sand than I tried in my last tank... ( still fine enough for the Cory's ) & also the earth eating Cichlids that are going in there... I'm hoping the thinnish layer, & the sand sifters will keep the sand moved around enough to prevent any bacteria pockets...

 

[gwand]

I have a substrate question. I am looking for a brand of black sand that will not harm bottom dwellers. What I see on line is mostly quarta-based sand that is too harsh. Any suggestions?

 

[AdoraBelle Dearheart]

I have a substrate question. I am looking for a brand of black sand that will not harm bottom dwellers. What I see on line is mostly quarta-based sand that is too harsh. Any suggestions?

I and @seangee both use the Unipac black limpopo sand, if that's available there? I have a lot of cories, two plecos, hasn't done them any harm, and Seangee checks things before he'd use them in his tanks very carefully.

 

[Magnum Man]

This is what I bought for the tank I'm setting up next...

Amazon.com

 

[TwoTankAmin]

According to all the major plant people who I hear speaking at my monthly club meeting or events, I should not have a single live plant surviving in my tanks. I pretty much refuse to buy almost anything specifically for aquarium plants. My CO2 system (I no longer have it) came from a beer supply outfit for the most part.

My club speaker last Friday was a dry start expert. She was a nice lady who worked in a store and is their plant person. I see zero reason to ever do things the way she laid them out. No dirt in my tanks, I use Jobes plant spikes for my gravel ferts. I plant my tanks with water in them. I have not found any plant I really wanted to keep in the proper tank that I could not have thrive.

I have basically not bough a new plant in about 15 years, maybe more. I have so many excess plants I even sell them when I do events.

But, the reason I do plants is that they can make the water healthier, they provide benefits to the fish including breaking up site lines. And plants can allow one to stock heavily if desired.

And the baxteria in the substrate is mostly beneficial, especially in planted tanks with substrate roots. If you want to understand how and why have a read of this paper:

Petersen Nils Risgaard-, Jensen Kim , (1997), Nitrification and denitrification in the rhizosphere of the aquatic macrophyte Lobelia dortmanna L., Limnology and Oceanography, 42, doi: 10.4319/lo.1997.42.3.0529.

Abstract​

Nitrogen and O2 transformations were studied in sediments covered by Lobelia dortmanna L.; a combination of 15N isotope pairing and microsensor (O2, NO3−, and NH4+) techniques were used. Transformation rates and microprofiles were compared with data obtained in bare sediments. The two types of sediment were incubated in doublecompartment chambers connected to a continuous flow-through system.

The presence of L. dortmanna profoundly influenced both the nitrification-denitrification activity and porewater profiles of O2, NO3−, and NH4+ within the sediment. The rate of coupled nitrification-denitrification was greater than sixfold higher in L. dortmnanna-vegetated sediment than in bare sediment throughout the light–dark cycle. Illumination of the Lobelia sediment reduced denitrification activity by ∼30%. In contrast, this process was unaffected by light–dark shifts in the bare sediment. Oxygen microprofiles showed that O2 was released from the L. dortmanna roots to the surrounding sediment both during illumination and in darkness. This release of O2 expanded the oxic sediment volume and stimulated nitrification, shown by the high concentrations of NO3− (∼30 µM) that accumulated within the rhizosphere. Both 15N2 isotope and microsensor data showed that the root-associated nitrification site was surrounded by two sites of denitrification above and below, and this led to a more efficient coupling between nitrification and denitrification in the Lobelia sediment than in the bare sediment.
https://aslopubs.onlinelibrary.wiley.com/doi/10.4319/lo.1997.42.3.0529

If the paper above is a bit intimidating, then try this instead:

Aquatic Plants and the Nitrogen Cycle
March 21, 2012 // by DrTim// Leave a Comment
https://www.drtimsaquatics.com/aqua...ticles/aquatic-plants-and-the-nitrogen-cycle/