adding a sand layer over existing soil

[Lioness]

I'm thinking of using Seachem Flourish as a nutrient layer in my planted Discus tank, but I want to cap it off with a sand substrate for easier waste management. Thing is, I'm worried the sand will just sift through the cracks in the Flourish - has anyone tried this before?

[Lioness]

Flourite is a better option for you, I think. It's designed to be a nutrient-rich substrate, so you can just use it on its own. I've used it in a few tanks and it's worked really well. You can cap it with sand, but I'd make sure the Flourite is at least 1-2 inches deep first. That way, you'll get the benefits of the substrate and the sand will stay on top.

[willie32]

I'm not convinced Flourite would stay separate from the sand long-term, might be worth exploring a dirted setup with pond compost instead. MD Fish Tanks has a great method, worth checking out his approach.

[Lioness]

I'm a fan of MD Fish Tanks too, but Seachem Flourish is more accessible for me. What about putting it in mesh bags first, then covering with sand?

[willie32]

I'm thinking of using Seachem Flourish as a nutrient layer in my planted Discus tank, but I want to cap it off with a sand substrate for easier waste management. Thing is, I'm worried the sand will just sift through the cracks in the Flourish - has anyone tried this before?

I think that's a better way to go. I've tried it in one of my tanks and it's worked out well. Have you considered using Wio Eonion? I've used it in one tank and I prefer it to other soils - it doesn't release ammonia at the start and it's designed for longer-term use. It claims to last 10 years, compared to the usual 1-3 years, whether that's true or not I don't know yet, but even if it's half of that it's a good thing.

[boomer]

For discus, I'm a firm believer in soft sand. The risks associated with soil just aren't worth it, if you ask me. I tried Flourite years ago, and let me tell you, it was a complete waste of money. My plants didn't seem to benefit from it after two years, and I had to remove my cories within the first week due to barbel erosion. The sharpness of the Flourite and the bacteria growth were just too much for them. I went back to play sand, and it was a game-changer - everyone, including the plants, were happy.

When you mix sand with any underlying substrate material, it's going to mix - it's just a matter of time. The smallest grain size, combined with gravity, water movement, and fish activity, will always cause the sand to settle and mix. I just don't think it's worth the risk to the fish.

[Lioness]

Good to hear that the mesh bag idea might work. For my discus, I'm planning a 405-litre tank and I'm thinking of getting 8. I've had experience with aggression in a smaller tank before, 200 litres with 5 discus was too small. This time the discus will be around 9-11cm, not full adults yet. The filter is 2000L/H, so I'm hoping that's enough. Does anyone think 8 is too many or just right?

[Lioness]

Also thinking of adding a school of cardinal tetras to the mix. Considering a clean-up crew, corys being a top choice for dealing with uneaten food - but I'm not sure if the bioload they'd bring would cancel out the benefits they'd provide.

[boomer]

I'm thinking of using Seachem Flourish as a nutrient layer in my planted Discus tank, but I want to cap it off with a sand substrate for easier waste management. Thing is, I'm worried the sand will just sift through the cracks in the Flourish - has anyone tried this before?

I think you'll have to rule out the corys for this tank, the temperature's just too high for them. Discus need it warm, around 26-30C, Cardinal tetras are fine with that, but corys aren't. Most discus keepers recommend keeping the temperature at least 80F, preferably a bit higher.

Corys just aren't suited for long-term life at those temperatures, they need it cooler, around 23-25C. And before anyone mentions it, even species like C. sterbai aren't warm-water corys.

The thing is, fish are ectothermic, their body temperature is controlled by the water temperature. It's what drives their metabolism, and a small change in temperature makes a huge difference to their well-being.

[WildFins]

I'm thinking of using Seachem Flourish as a nutrient layer in my planted Discus tank, but I want to cap it off with a sand substrate for easier waste management. Thing is, I'm worried the sand will just sift through the cracks in the Flourish - has anyone tried this before?

The temperature issues aside, I think there's a misconception about corys being a clean-up crew. They do feed on substrate food, but they won't magically keep the tank clean for us. At best, the results would be underwhelming. More importantly, corys have specific dietary needs that aren't met by just eating leftover food. They're wonderful fish, don't get me wrong - peaceful, unique, fun to watch, and great for the bottom of the tank. But let's not expect them to do our job for us. Maintaining the tank is always on us.