Who Gives A Fish Forums

Hi, I'm new to fish keeping and I'm downsizing from a 125l fluval to an 80L super fish tank. I didn't have many live plants in my old tank, but I want more in my new one. I'd love some advice on how to do this.

What type of soil should I get for my plants? I've seen people recommend using sand on top of the soil instead of gravel, as gravel can sink into it. Should I get normal sand or is there a special type I should use?

I'd appreciate any advice, don't worry about being too detailed or not detailed enough. I have betta fish, plecs, and 2 baby hoplo catfish, so I want to make sure I get it right.

My main questions are: what soil should I use, what sand should I use, and do I need to add anything to the soil to help the plants grow faster? Also, do I need to let the tank settle before adding my fish?

I asked on a Facebook group if I need to cycle the tank, and someone said I can just transfer my old filter media to the new one and it'll be cycled. Is this right? And is a soil tank harder to maintain than a gravel tank?

I'm not sure you need to go down the soil route unless you're planning a high-tech aquarium with some of the more challenging plants, CO2 injection and just a few fish. For a standard fish tank with plants, sand or gravel will do the job just fine. You can supplement with liquid fertiliser and/or root tablets, depending on the type of plants you're keeping.

I've found that some soils can leach ammonia for months, which means you'd have to wait until that stops before introducing your fish. Others seem to run out of nutrients after a year or so and essentially become the same as plain sand or gravel. To be honest, a lot of us just stick with a plain substrate and add fertiliser as needed.

Regarding cycling, it's worth noting that the beneficial bacteria live on every surface in the tank, not just the filter. So, the more you can transfer - filter, decor, substrate and all - the better. Your current plants are likely using some of the ammonia produced by your fish, which means there are fewer bacteria than there would be in a tank with no live plants. With a lot of live plants in your new 80-litre tank, they'll help absorb a lot of the ammonia, making it easier to cope with any bacteria lost during the move.

Will your new 80-litre tank be going in the same spot as your current 125?