Who Gives A Fish Forums

finnley9 wrote: ↑Fri Jun 20, 2025 11:04 am Does anyone use a filter sock in their sump? I've heard mixed things about whether they're necessary for coral tanks.

I use them but swap them out every 3 days to avoid nitrate buildup. They're great for mechanical filtration but can become a nutrient trap if neglected.

For a 75-gallon tank, I'd recommend a 30-gallon sump. It gives you enough space for a skimmer, refugium, and return pump without cramming everything. I run a 30-gallon sump on my 80-gallon system, and it's been perfect for maintaining stable params. Just make sure your baffles are spaced right to ...