[rotachoc]

Hi all,
I have a african cichlid tank with sump,
In the sump i'm running 5kg of Maxspect Bio-Spheres as my media.
My questions,
Is it ok to add 5kg or more of lava rock as an addition to the Maxspect Bio-Spheres???
Will it change the water parameters much (ph/gh/etc,etc.???
cheers and
Happy Easter

:fish:

 

[SoccerMbunaAndShak]

Hey rotachoc!
Lava rock will 99% of the time not have an impact on water chemistry. The very few times it does is if there are mineral deposits on it. You can spot these by just looking at them, and partially prevent them by using smaller pieces. However, the huge benefit that you get in terms of biological filtration far outweigh the risk, IMO. So I think that if you have the space for it in your sump, go for it. Likely won't hurt. Also, consider how much livestock you have. If you have a lower stocking level, I think the biospheres will do the trick and there will be no need for the lava rock. If you have higher stocking levels, you may want to use the lava rock.