Blackwater substrate

[Tropicalfishkeeping201]

Hello fishkeepers,

I will be setting up my first 7 gallon blackwater cube tank for my one betta.

I wanted to know if you can use Aquarium soil or organic potting mix soil topped with a thin layer of sand in a Blackwater tank or should sand only be used? 

I heard something about that gasses can build up in the substrate so I want to make sure I create a safe environment and not cause any issues for my betta. 
 

Thank you in advance

 

[Lennie]

I use tropica aquasoil in my setups and never cap it. If you like planting your tanks you can use aquasoil. (Not as a dirted walstad tank setup tho, normal planted tank setups)

however, keep that in mind, with aquasoil you will need to do lots of water changes before it stops leeching ammonia. So if you are okay with waiting for a month or so and willing to make lots of water changes, than it should be fine I guess. I usually plant heavily on day one, do big water changes every two days for 3 weeks. Introduce established filter run it until I see no ammonia/nitrite and add my fish in.
 

The thing is, in blackwater setups, the light is blocked a lot due to the dark color of the water. I believe that’s why people mostly go for rhizome plants which usually do well under very dim light. So I am not sure how much you can utilize aquasoil and root feeders in a true blackwater setup. 
 

 

Edited April 9, 2023 by Lennie

[AllFishNoBrakes]

Here’s my blackwater tank. It started as a shrimp only tank about 3 years ago. Over the past couple of weeks I’ve been loading it up with botanicals and tannins:

In person it looks much darker. I’m really diggin’ this tank and trying something new has been really fun. 
 

Here’s my dirted tank. It’s about a year and a half old:

The Pearl Weed has taken over, but I love it. 
 

On 4/9/2023 at 1:25 AM, Lennie said:

The thing is, in blackwater setups, the light is blocked a lot due to the dark color of the water. I believe that’s why people mostly go for rhizome plants which usually do well under very dim light. So I am not sure how much you can utilize aquasoil and root feeders in a true blackwater setup. 

Agreed with this! For this reason, I personally wouldn’t combine both styles of tanks. For my blackwater setup I’m gonna go with a couple Anubius and call it a day. For now, I’m just digging the tannins and seeing how the shrimp and snails react to the new environment. When I find some nice Anubius locally I’ll snatch them up and add them in. 
 

When it comes to your tank, do whatever you want! That’s the beauty of keeping an aquarium; you can do exactly what you want with it. I also think that if you’re going for a light tint in your water, that won’t block out as much light and then maybe the aquasoil/dirt makes more sense. I’m personally going for a dark tint to the water. 

[Lennie]

On 4/9/2023 at 6:38 PM, AllFishNoBrakes said:

Here’s my blackwater tank. It started as a shrimp only tank about 3 years ago. Over the past couple of weeks I’ve been loading it up with botanicals and tannins:

In person it looks much darker. I’m really diggin’ this tank and trying something new has been really fun. 
 

Here’s my dirted tank. It’s about a year and a half old:

The Pearl Weed has taken over, but I love it. 
 

Agreed with this! For this reason, I personally wouldn’t combine both styles of tanks. For my blackwater setup I’m gonna go with a couple Anubius and call it a day. For now, I’m just digging the tannins and seeing how the shrimp and snails react to the new environment. When I find some nice Anubius locally I’ll snatch them up and add them in. 
 

When it comes to your tank, do whatever you want! That’s the beauty of keeping an aquarium; you can do exactly what you want with it. I also think that if you’re going for a light tint in your water, that won’t block out as much light and then maybe the aquasoil/dirt makes more sense. I’m personally going for a dark tint to the water. 

Very pretty, If I wasn't living in the middle of the city and/or botanicals were not that pricey, I would love to try a blackwater setup too! 

For now, all I can do is putting 1-2 catappa leaves and 3-4 alder cones for the tannin benefits 😄 

[AllFishNoBrakes]

On 4/9/2023 at 9:45 AM, Lennie said:

Very pretty, If I wasn't living in the middle of the city and/or botanicals were not that pricey, I would love to try a blackwater setup too! 

Thanks! I wish I could get a good picture showing how dark the tank looks in person. Especially next to all my bright, planted tanks. 
 

Idk where you’re located, but I got bulk IAL’s on Amazon for what I felt was a fair price, and a box of like 139 botanical pieces off Etsy. Together they were ~$50, but that box of botanicals will last for a looooong time. 
 

Blackwater is definitely different than all my other 13 planted tanks, but I’m digging it. Some wood, some tannins, boom bam you have a great looking tank. 

[Tropicalfishkeeping201]

Thank you so much @Lennie and @AllFishNoBrakes 🙂 

On 4/9/2023 at 11:38 AM, AllFishNoBrakes said:

Here’s my blackwater tank. It started as a shrimp only tank about 3 years ago. Over the past couple of weeks I’ve been loading it up with botanicals and tannins:

On 4/9/2023 at 11:38 AM, AllFishNoBrakes said:

In person it looks much darker. I’m really diggin’ this tank and trying something new has been really fun

Wow, This is a very pretty tank! Love it!  This is the look I want in my cube tank