# Sand vs gravel



## Sarpijk (7 Jun 2022)

Hi everyone, just wanted to discuss whether sand is better for capping a soil substrate. Having used both I must say that for some reason sand seems to yield better results for me.

For example I got a Tropica pot of Lagenadra and put some plants in the gravel substrate and some to the sand one. Both tanks have the same type of soil underneath and are both low tech. While the plant in the gravel substrate has all but melted, in the sand substrate is growing huge. Cryptocoryne Nurii also seems to prefer sand.

Is it possible the sand locks in the nutrients better ?


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## Wookii (8 Jun 2022)

I have found similar to you @Sarpijk - I have found some plants, particularly crypts, seem to grow better with much less melt, when I've used a 40-50mm deep cap of fine sand over aquasoil, versus planting straight into bare aquasoil.


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## dw1305 (8 Jun 2022)

Hi all, 


Sarpijk said:


> Is it possible the sand locks in the nutrients better ?


Rather than locking them in, I wonder if <"nutrients are more available">, because you are more likely to have zones of fluctuating REDOX values (in the rhizosphere) with sand as a capping. 

cheers Darrel


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## Courtneybst (8 Jun 2022)

This is really good to know! One of the many reasons I love UKAPS.


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## Sarpijk (8 Jun 2022)

To illustrate the difference in growth I give you Lagenadra in sand 








and the sad specimen in the gravel tank


.


Of course I realise many other factors could be at play but the overall idea is that all plants that I have used in sand do better in most cases.


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## Courtneybst (8 Jun 2022)

Sarpijk said:


> To illustrate the difference in growth I give you Lagenadra in sand
> 
> 
> 
> ...


Is this pure sand or enriched with anything else?


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## Sarpijk (8 Jun 2022)

Courtneybst said:


> Is this pure sand or enriched with anything else?


Both tanks have a layer of sifted potting soil underneath. I use Tropica specialised for the water column.


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## FirstClassFish (28 Jun 2022)

Sarpijk said:


> Hi everyone, just wanted to discuss whether sand is better for capping a soil substrate. Having used both I must say that for some reason sand seems to yield better results for me.
> 
> For example I got a Tropica pot of Lagenadra and put some plants in the gravel substrate and some to the sand one. Both tanks have the same type of soil underneath and are both low tech. While the plant in the gravel substrate has all but melted, in the sand substrate is growing huge. Cryptocoryne Nurii also seems to prefer sand.
> 
> Is it possible the sand locks in the nutrients better ?


Very interesting. What kind of sand do you use?


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