Black or natural sand?

[Treestone]

First thing to get clear is the needs of certain fish species with respect to the substrate. Corydoras catfish were mentioned, and these are filter feeders. They take in a mouthful of sand, filter out tiny food bits, and expel the sand via the gills. Some sand is also swallowed with the food. These fish all live over substrates of fine river sand or mud, or a combination. They are filter feeders, and if we care about the wellbeing of our fish we must be willing to provide accordingly. You can appreciate what risks are present if we put a rough sand in the aquarium with such fish.

That's one factor. Another that is related to sharpness/roughness is the barbel erosion risk. Self-obvious. And then there is the bacterial issue. The larger the grain size of the substrate, the less efficient is the breakdown of organics by bacteria. This causes bacterial issues for catfish barbels.

To the black sand...fish react to the substrate. Corydoras maintained over white substrates will have less intense colouration because of the substrate. The same works in reverse; black is not "natural" and the fish internally react and may darken their body colouration. In both cases it is a response of the fish to adverse (stressful) conditions brought on by the substrate. The fish has no control, this is something of an automatic reflex.

Aquarists often confuse what they want with what their fish require.

I thought it was a matter of feeling safer over a black substrate that the fish have more pronounced colours and over a bright substrate they feel unsafe and therefore stressed. My only problem with what your saying is a black substrate isn't naturally occurring. Iron sand appears in multiple areas around the world. In a heavily hardscaped/or planted tank would this be such an issue?

 

[WhistlingBadger]

@Treestone, no, I do not believe it is an issue. Very dark/black substrates do appear in nature, and I have kept fish successfully for multiple years over black sand, with excellent coloration, excellent health, and natural behavior. Likewise with the so-called "abrasive" sands. My experience, and the experience of many others, says that it does not cause health problems. Certainly smoothed, naturally colored sands don't hurt; they certainly replicate more closely the most common natural conditions. If using such feels safer to you or confirms your reading/experience/intuition, I would advise going that direction.

That said, @Byron, respectfully, I wish you would stop implying that those who come to different conclusions than you don't care about the needs of their fish. That is disrespectful, unkind, and untrue. You are not the only one who does research, sir.

 

[CassCats]

Play sand is nice and cheaper. Dark sands are nice but ive seen some cory colours on black sand where they were so dark they looked smudged. Just seems very odd to look at a normally shiny silver trilineatus and see it look like soot lol but that's my personal preference.

 

[Kelp23]

I've just set my tank up with black fine gravel. I love the colour but you can see the poop on the top so I've bought a Turkey baster and I'm going to just try and regularly collect it up

 

[seangee]

I've just set my tank up with black fine gravel. I love the colour but you can see the poop on the top so I've bought a Turkey baster and I'm going to just try and regularly collect it up

That looks similar to the sand I use. When I first switched to sand I used to religiously clean it every day, especially as I have high nitrates in my tap water, which I was using at the time. Members on this site told me not to bother as I had plants and bacteria would quickly develop to assist in cleaning the sand. I was sceptical but it turned out they were correct. Within a week my sand looked like a newly swept beach every morning. I did add some Malaysian trumpet snails, these eat poop and turn it into much smaller poop which the bacteria deal with far quicker. Nowadays the only thing I ever clean off the sand is dead leaves, despite the fact that one of my tanks has a fully grown (16 year old) bristlenose and another has a nerite, both of which are generally regarded as poop machines..

Naturally you have to be careful to avoid overfeeding, and I only use premium foods that contain much less filler than some of the less expensive products, even the well known brands. Less filler means less waste that the fish can't digest. Fish eat so little the price difference really is not a factor.

The picture in my signature was taken about 6 months after changing my sand (I only changed because I wanted a dark substrate). It has never been cleaned. When I did change my sand after about 5 years I was a bit nervous about what I might find lurking in there. I needn't have worried - it was surprisingly clean throughout with no bad smells or suspect patches.

 

[Kelp23]

That looks similar to the sand I use. When I first switched to sand I used to religiously clean it every day, especially as I have high nitrates in my tap water, which I was using at the time. Members on this site told me not to bother as I had plants and bacteria would quickly develop to assist in cleaning the sand. I was sceptical but it turned out they were correct. Within a week my sand looked like a newly swept beach every morning. I did add some Malaysian trumpet snails, these eat poop and turn it into much smaller poop which the bacteria deal with far quicker. Nowadays the only thing I ever clean off the sand is dead leaves, despite the fact that one of my tanks has a fully grown (16 year old) bristlenose and another has a nerite, both of which are generally regarded as poop machines..

Naturally you have to be careful to avoid overfeeding, and I only use premium foods that contain much less filler than some of the less expensive products, even the well known brands. Less filler means less waste that the fish can't digest. Fish eat so little the price difference really is not a factor.

The picture in my signature was taken about 6 months after changing my sand (I only changed because I wanted a dark substrate). It has never been cleaned. When I did change my sand after about 5 years I was a bit nervous about what I might find lurking in there. I needn't have worried - it was surprisingly clean throughout with no bad smells or suspect patches.

Oh brill. That's good to know. I have a nerite snail but I'm reluctant to put him in this tank as I also have 2 blue lobster and a Hoplo catfish. Im having to be really careful with feeding as the lobsters, catfish and normal fish all eat different foods so I'm putting 3 lots of food into the tank. It's a new set up too so if I underfeed there isn't much in there for them to find. I think I'll certainly invest in some better quality food when my current food runs out.

 

[WhistlingBadger]

That looks similar to the sand I use. When I first switched to sand I used to religiously clean it every day, especially as I have high nitrates in my tap water, which I was using at the time. Members on this site told me not to bother as I had plants and bacteria would quickly develop to assist in cleaning the sand. I was sceptical but it turned out they were correct. Within a week my sand looked like a newly swept beach every morning. I did add some Malaysian trumpet snails, these eat poop and turn it into much smaller poop which the bacteria deal with far quicker. Nowadays the only thing I ever clean off the sand is dead leaves, despite the fact that one of my tanks has a fully grown (16 year old) bristlenose and another has a nerite, both of which are generally regarded as poop machines..

Naturally you have to be careful to avoid overfeeding, and I only use premium foods that contain much less filler than some of the less expensive products, even the well known brands. Less filler means less waste that the fish can't digest. Fish eat so little the price difference really is not a factor.

The picture in my signature was taken about 6 months after changing my sand (I only changed because I wanted a dark substrate). It has never been cleaned. When I did change my sand after about 5 years I was a bit nervous about what I might find lurking in there. I needn't have worried - it was surprisingly clean throughout with no bad smells or suspect patches.

That's very much what I've found, too. Sometimes I'll get a little bit of mulm in low spots, but in a naturally decorated tank, that isn't a problem. If it looks bad, it's easy enough to remove.

 

[PheonixKingZ]

That's very much what I've found, too. Sometimes I'll get a little bit of mulm in low spots, but in a naturally decorated tank, that isn't a problem. If it looks bad, it's easy enough to remove.

The only reason why I clean the sand so often in my 29g tank, is because I have a BNP and a Nerite snail. They are SO messy.

I usually never touch the sand in my 5g, 10g, or 20g long tank.

 

[Byron]

I thought it was a matter of feeling safer over a black substrate that the fish have more pronounced colours and over a bright substrate they feel unsafe and therefore stressed. My only problem with what your saying is a black substrate isn't naturally occurring. Iron sand appears in multiple areas around the world. In a heavily hardscaped/or planted tank would this be such an issue?

We were discussing substrate for Corydoras. The OP asked about that, and I was providing information based upon the habitats. As for black, if you research fish habitats you will find that "dark" is the key, not black. Most of the sand in tropical waterways is the buff-tone we are all familiar with as common beach type sand. In some watercourses it can be a dark grey tone. No where is it black that I have ever come across (certainly not in South America where we find the Corydoras species), and if you or anyone can provide evidence to the contrary, I would be glad to look into it.

The reason the substrate is "dark" and always recommended to be "dark" in the aquarium is due more to the light level. Tropical watercourses are usually shaded by forest canopy. The larger rivers do have direct sun, but the fish we all maintain in our tanks do not occur in these open waters but in shaded tributaries, under marginal vegetation, etc. The layer of dead leaves which cover many of the channels add to the "dark" because what little light does get through is not enough to be reflected back.

I'd be interested in what "iron sand" refers to; if you mean the reddish substrate clay of some watercourses in SE Asia, that is something else again.

And @WhistlingBadger, my advice is taken from the knowledgeable sources that have spent years in these habitats. Ian Fuller likely knows more about cories than all of us here put together. You can tell him he is mistaken over this if you like, but I shall use his wisdom to provide advice, for the good of the fish.

 

[Kelp23]

The only reason why I clean the sand so often in my 29g tank, is because I have a BNP and a Nerite snail. They are SO messy.

I usually never touch the sand in my 5g, 10g, or 20g long tank.

Do you think I would be best to leave my nerite snail in my other tank then with my baby platies? I was worried about my Lobsters having him for breakfast

 

[PheonixKingZ]

Do you think I would be best to leave my nerite snail in my other tank then with my baby platies? I was worried about my Lobsters having him for breakfast

I have no advice with lobsters, so I can not give any advice.

@Byron, do you know?

 

[Essjay]

I would not keep lobsters in any tank which has fish in or you may find them disappearing one by one. There is a saying "fins and claws don't mix" for a good reason.

Whether they would eat snails or not, I don't know.

 

[Kelp23]

I would not keep lobsters in any tank which has fish in or you may find them disappearing one by one. There is a saying "fins and claws don't mix" for a good reason.

Whether they would eat snails or not, I don't know.

They dont seem to bother with the fish to be honest. If one swims and lands on it they wave their arms about a bit but that's about it. They just annoy each other. I have a second tank and I can move things around if they start being naughty but I do a headcount each morning and everyone is still there

 

[Treestone]

We were discussing substrate for Corydoras. The OP asked about that, and I was providing information based upon the habitats. As for black, if you research fish habitats you will find that "dark" is the key, not black. Most of the sand in tropical waterways is the buff-tone we are all familiar with as common beach type sand. In some watercourses it can be a dark grey tone. No where is it black that I have ever come across (certainly not in South America where we find the Corydoras species), and if you or anyone can provide evidence to the contrary, I would be glad to look into it.

The reason the substrate is "dark" and always recommended to be "dark" in the aquarium is due more to the light level. Tropical watercourses are usually shaded by forest canopy. The larger rivers do have direct sun, but the fish we all maintain in our tanks do not occur in these open waters but in shaded tributaries, under marginal vegetation, etc. The layer of dead leaves which cover many of the channels add to the "dark" because what little light does get through is not enough to be reflected back.

I'd be interested in what "iron sand" refers to; if you mean the reddish substrate clay of some watercourses in SE Asia, that is something else again.

And @WhistlingBadger, my advice is taken from the knowledgeable sources that have spent years in these habitats. Ian Fuller likely knows more about cories than all of us here put together. You can tell him he is mistaken over this if you like, but I shall use his wisdom to provide advice, for the good of the fish.

Iron sand (aka black sand) is mainly composed of magnetite is a dark black sand occurring on many beaches around the world (I don't know if it occurs in any freshwater systems but there may be overlap)(is very similar if not @seangee 's sand).

I agree with your statement here, yet a couple of posts back you said

Darker is better, but pure black is not all that good for fish, including some mentioned here.

you then reply to my message in less general terms specifically about corydoras yet this is a very broad statement. Without going into detail about corydoras or similar bottom dwellers what is your basis for this? Define what you mean by black sand because I have a feeling our ideas of it are quite different.

 

[Bub]

Do you think I would be best to leave my nerite snail in my other tank then with my baby platies? I was worried about my Lobsters having him for breakfast

Crayfish do tend to eat snails, and while nerites stand a better chance than most, I wouldn't keep them together personally. Also, lobsters are saltwater, if it's in freshwater it is a crayfish.