Substrate and Blackwater setup questions

Barry Tetra

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Hi everyone, here’s the questions;
1. Is there anyway to move substrate from gravel to sand without moving any fishes? (Discus tank)
2. does play sand increase pH level? is this dangerous to discus and angel?
3. I always wanted to do Blackwater tank (inspired by @seangee post “back to black”) but the Indian almond tree are far from home and we are in quarantine :(
Tetra Blackwater Extract are damn expensive in my country
4. How to clean sand in water changes?
5. Will blackwater affect the plants?
 
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Gravel clean the substrate one day. The following day use a fish net to scoop the gravel or sand out of the aquarium. If it's a big tank (3 foot or longer), you can leave the fish in the tank when you do this. In small tanks it's better to remove the fish, then remove/ replace the substrate, then put the fish back in.

Turn the filter off when you do this if you are removing or adding sand to stop sand being sucked into the filter. Leave the filter on if you are doing gravel.
 
Hi everyone, here’s the questions;
1. Is there anyway to move substrate from gravel to sand without moving any fishes? (Discus tank)
2. does play sand increase pH level? is this dangerous to discus and angel?
3. I always wanted to do Blackwater tank (inspired by @seangee post “back to black”) but the Indian almond tree are far from home and we are in quarantine :(
Tetra Blackwater Extract are damn expensive in my country
4. How to clean sand in water changes?
5. Will blackwater affect the plants?

Q1; As above, clean the gravel out one day. Then the next, use the net to scoop it out.

Q2;. No, play sand shouldn't increase pH. However, if you want to be sure, when you rinse it (and it should always be rinsed), leave it to stand in the bucket overnight and check the pH level.

Q3; Try eBay for almond leaves - they should deliver, but you may have to wait a while (I'm still waiting for some driftwood that I ordered nearly 2 weeks ago).

Q4;. More or less the same way you clean gravel - just be careful not to vacuum the sand up.

Q5;. It's never affected mine.
 
Wash the sand before starting to remove the gravel.

Play sand should not affect the pH. It is sand made from coral or limestone rocks that will change pH - and GH and KH. If you are worried fill two tubs with water and put some sand in one of them. Leave them to stand for a week. Then test the pH of both tubs. if they are the same, the sand is good to use. The tub with no sand is so that you can compare plain water to the water with sand in after they have both stood for the same time.


I have sand and I clean the sand by having the end of the tube about 1 cm above the sand and make little swirling movements to lift the mess off the sand so it can be sucked up.


FishkeeperLinz posted as I was typing :)
 
Just leave the gravel in the tank unless you want catfish or loaches, which do better with sand or smooth gravel.

If you have some driftwood in the tank it should release tannins and stain the water yellow or brown (blackwater). You can also use peat moss and put some in a fine mesh bag and put it in the filter.

Personally, I don't see any point in having blackwater in an aquarium unless you are trying to breeding wild caught fish. It simply makes it too hard to see the fish.

Blackwater will reduce the amount of light that gets to the bottom of the tank and plants can suffer from the lower light levels. Blackwater can also cause the pH to drop and some plants don't do that well in acid water.
 
3. I always wanted to do Blackwater tank (inspired by @seangee post “back to black”) but the Indian almond tree are far from home and we are in quarantine :(
Tetra Blackwater Extract are damn expensive in my country
Most of my pics in that thread are not actually blackwater. It is an environment suitable for blackwater fish but the only tannins are what come out of the driftwood - and there is quite a lot in there. Having said that the wood has been in the tank for a long time so does not leach too much tannin and the water is only mildly discoloured by the time the weekly water change comes around. Most of the effect comes from the dark substrate and heavy growth of floating plants. I am experimenting with adding tannin at the moment but as @Colin_T says this has a really big impact on lighting and is not essential.

I did post somewhere the technique I used for replacing the substrate in that tank without removing the fish (you will have to search :)) but for a smaller tank it is easier just to take the fish out.

Finally on cleaning sand I don't and the system as a whole means it stays clean. By system I mean biological ecosystem - not the equipment I have in the tank, which is actually quite minimal. This can be the cause of heated arguments on this forum and others so lets not start one and just say that some people vacuum their sand and some don't. Both approaches are valid as long as your sand stays clean and does not create dirty water (or bad smells) when it gets disturbed.
 
Most of my pics in that thread are not actually blackwater. It is an environment suitable for blackwater fish but the only tannins are what come out of the driftwood - and there is quite a lot in there. Having said that the wood has been in the tank for a long time so does not leach too much tannin and the water is only mildly discoloured by the time the weekly water change comes around. Most of the effect comes from the dark substrate and heavy growth of floating plants. I am experimenting with adding tannin at the moment but as @Colin_T says this has a really big impact on lighting and is not essential.

I did post somewhere the technique I used for replacing the substrate in that tank without removing the fish (you will have to search :)) but for a smaller tank it is easier just to take the fish out.

Finally on cleaning sand I don't and the system as a whole means it stays clean. By system I mean biological ecosystem - not the equipment I have in the tank, which is actually quite minimal. This can be the cause of heated arguments on this forum and others so lets not start one and just say that some people vacuum their sand and some don't. Both approaches are valid as long as your sand stays clean and does not create dirty water (or bad smells) when it gets disturbed.
This is what I wanted my tank to looklike (picture from google btw)
 

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You want to use a dark-tone sand, not white or even light because light is reflected off a light-tone substrate and this bothers the fish. Floating plants are always benefgicial here, because they do the useful job of keeping water conditions good [plus they further shade the light. A good layer of dried leaves on the substrate will also help with all this.

On the initial question of changing the substrate, consider: netting out the fish to a temporary tank and then netting them back when the existing tank is finished is obviously stressful. However, tearing aprat the entire tank with the fish left petrified without refuge and shaking with fear or darting all over the tank looking for refuge is even more stressful. And to change the substrate, you need to remove all decor (the refuge) and plants if any, and take out most all of tyhe existing gravel before you can add the sand or it will mix and be a mess. I have changed substrates dozens of times, and I always move the fish into a nice temporary tank with some of their decor, and the plants, and they can stay there for a day or two days or three days so I can properly do the job without being rushed. And the fish are quite settled in their temporary home. The filter and heater should be moved over obviously.
 
You want to use a dark-tone sand, not white or even light because light is reflected off a light-tone substrate and this bothers the fish. Floating plants are always benefgicial here, because they do the useful job of keeping water conditions good [plus they further shade the light. A good layer of dried leaves on the substrate will also help with all this.

On the initial question of changing the substrate, consider: netting out the fish to a temporary tank and then netting them back when the existing tank is finished is obviously stressful. However, tearing aprat the entire tank with the fish left petrified without refuge and shaking with fear or darting all over the tank looking for refuge is even more stressful. And to change the substrate, you need to remove all decor (the refuge) and plants if any, and take out most all of tyhe existing gravel before you can add the sand or it will mix and be a mess. I have changed substrates dozens of times, and I always move the fish into a nice temporary tank with some of their decor, and the plants, and they can stay there for a day or two days or three days so I can properly do the job without being rushed. And the fish are quite settled in their temporary home. The filter and heater should be moved over obviously.
Can I use sea sand? we have sea sand.
 
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Beach sand is made from calcium and will raise the pH. It's fine for a salt water aquarium or an African Rift Lake tank, but not suitable for soft water fishes.
 
I prefer fine brown gravel but other people prefer sand. The choice is yours as to which you prefer. Darker substrates are better than light coloured substrates.

If you have loaches, eels or catfish, then use sand or smooth gravel.
 
I prefer fine brown gravel but other people prefer sand. The choice is yours as to which you prefer. Darker substrates are better than light coloured substrates.

If you have loaches, eels or catfish, then use sand or smooth gravel.
Do you think how many kg of sand for 50 Gal tank? @seangee @Colin_T
 
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What is the length and width of the tank?
How thick do you want the sand?
 

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