Hot-swapping sand for aquasoil

[jgh44]

Hi all. I’m hoping to get some advice about swapping out sand substrate in a 20 gallon freshwater planted and fully stocked tank for a soil-like substrate like aqua soil.

I’ve read that doing this will cause a drastic ammonia spike that will kill the fish. I have an idea to avoid this that I’d like advice about.

I have a 10 gallon tank I’m not using. I could put the amount of soil substrate into the 10 gallon tank that I’d eventually want in the 20 gallon tank, add water and a bacteria starter and begin a cycle using some fish food or pellets. When the water levels look healthy and stable, I would empty out 1/2 of the water in the 20 gallon tank, replace the sand with the soil from the cycled 10 gallon tank, fill up the 20 with water from the 10 gallon tank and thus skip the ammonia spike. I could also use some of the filter media from the 10 in the 20 to help with stability and cross-tank bacteria support.

The fish would remain in the 20 gallon tank the whole time except possibly when I actually change out the substrate.

Any advice appreciated.

Peter

 

[ZxC]

That will work, here are my take away's:

1) Skip adding fish food into the cycling tank, AquaSoil will release ammonia and no fish food is required.
2) If you fully cycle the substrate, ensure you keep a close eye on the water parameters once you swap it into the new tank.
3) Adding some cycled media will hlep speed things up

Lastly, why are making the switch? Any and all plants will grow just as good in sand, so no need to swap. But if you have your reasons to swap, then yes you will need to cycle it.

 

[jgh44]

Thanks so much! My reason is in part because I've read that plants will grow better in aquasoil - something that I'll question based on your advice - and aesthetics. The sand is white and even a little debris makes it look unattractive. My thought is that more plants spread through the substrate would eliminate this and also make the tank conditions more healthy from a nitrate perspective. Any thoughts welcome.

 

[ZxC]

Thanks so much! My reason is in part because I've read that plants will grow better in aquasoil - something that I'll question based on your advice - and aesthetics. The sand is white and even a little debris makes it look unattractive. My thought is that more plants spread through the substrate would eliminate this and also make the tank conditions more healthy from a nitrate perspective. Any thoughts welcome.

Plants will grow without issue in plain sand, no substrate fertilization is required so long as the water column nutrition is met.

For aesthetics, that is your call. You can swap out to any other substrate (that doesn't leach ammonia) without having to cycle it. Worth looking into.

Aquasoil is a buffering substrate, so your pH will drop and kH will drop until you exhaust it's buffering ability (assuming you aren't using RO / distilled water).

Plants spreading through substrate is easily achievable in plain sand or fine gravel, aquasoil as well. Cleaning the substrate is much easier done with sand or gravel, almost impossible with aquasoil.

What are your goals with this tank?
What equipment are you running? (Lighting, CO2, filtration)
What fertilizers are you running / plan to run? And how much how often?
How large are your water changes, and how often?

 

[fearlessfisch]

I just did exactly the opposite in one of my tanks. I started with soil, thinking that it would help with plants, but found it so messy that I pitched it within a week or two. Reading from people here that plants do just fine in sand was the clincher for me.