# Cheap capping substrate (crushed lava rock)



## Ryan Young (27 Feb 2017)

Anyone know whether this stuff would be good capping a soil substrate to grow plants such as lobelia cardinalis and eleocharis acicularis whilst not disturbing the soil- https://www.amazon.co.uk/crushed-La...&qid=1488225728&sr=1-11&keywords=2-3mm+gravel

I was going to use pool filter sand but the colour would not work.

Thanks, Ryan


----------



## roadmaster (28 Feb 2017)

My only concern would be how sharp the material might be for tiny root's?


----------



## Ryan Young (1 Mar 2017)

I reckon in terms of how sharp it is it would be ok as it would be similar to eco complete substrate but am not sure whether it will be inert or if something would have been added to it?


----------



## roadmaster (1 Mar 2017)

No,I have used Eco-complete and the bag's I used were not as sharp/rough as lava rock which I have used in the past, till I noted pleco's scraping their bellies raw while scouring over the lava rock.
The lava rock I used was large pieces with anubia attached to them.


----------



## alto (1 Mar 2017)

EC is really quite smooth, Flourite is much sharper, crushed lava I've touched (garden shop) was in a league of its own 
Particle size looks quite variable, while established plants may invade such substrate, establishing a plant in this sort of substrate is more challenging - how big is the tank?


----------



## Ryan Young (1 Mar 2017)

Hmm, maybe a sand would be more suitable, the tank is 90 x 30 x 45


----------

