One 7 in vs two 4 in filter socks?

[BigWillStyle]

Hey! I am in the market for a sump for my fiji 76 shallow I just bought. I was going to go with my default brand of eshopps and their AF-200 but then the Fiji 30 option looked interesting with the integrated mounts. The main difference is the fiji uses 2 x 4 in socks while the eshopps uses a 7 in. I run both but I am genuinely curious if anyone has done any studies or comparisons on which is better. Does the slight increase in surface area actually justify all the extra work of swapping/washing two? Is the flow better on the single 7 that allows for less maintenance without the phosphates rising?

I run my 40 off a single 4 in, 50 on a single 4 in, 120 on two 4 in and a 150 on one 7 in. Interested in what y'all thinks is best.

 

[Timfish]

Since fish poop is an important part of the carbonate cycle on reefs I'd suggest not using any mechanical filtration and just occasionally, > yearly, siphoning out most, but not all the detritus that accumulates in the sump.

Fish Guts Explain Marine Carbon Cycle Mystery

Research reveals the major influence of fish on maintaining the delicate pH balance of our oceans, vital for the health of coral reefs and other marine life. The discovery could help solve a mystery that has puzzled marine chemists for decades. Published in Science, the study provides new...

www.sciencedaily.com

 

[BigWillStyle]

well that would lend itself to the FIJI. One thought on that, a very active fuge would be required without any mechanical filtration. Of the two sumps the AF-200 has a much larger sump volume, especially when you consider it stays filled and is not dependent on skimmer depth