LR or DSB in fuge

[Bayou]

I have a DSB in the fuge section of my sump. It is 20" wide, 12" across and about 5" of sand.
I'm debating taking all the sand out and putting rubble LR in its place. I think it would buffer the water better and keep my pH a little more stable and make it higher(I topoff lime water to keep it between 8.0 and 8.1.)
When Marc did his presentation at the meeting a few months back he said a DSB this small will do almost no good. Plus there is always the risk of it crashing your tank.

Anyone have an opinion?

 

[psteeleb]

the rubble won't enough density to it to contain anaerobic bacteria to breakdown nitrate like the live rock or dsb will

 

[DaveJ]

@Bayou wrote:

Its effectiveness could be questionable but I think one that size could help reduce your nitrates though not as much as might be needed depending on your bioload. As far as crashing your tank, I think that particular concern is overblown provided you maintain the DSB and just let it sit... since the size is smaller, you'll need to keep on top of things re-seeding occasionally etc.

For the pH... I don't know if one would help over another.. low pH is not a volume or makeup issue usually. Swapping LR over the DSB I don't think will have an impact on pH at all and the buffering qualities of LR or Sand is minimal.