Is the only point of a sump baffle to raise the water level for a skimmer?

[strich]

I'm currently looking into DIYing my own sump and I'm finding myself asking a lot of basic questions about the standard design I see everywhere. In this case it seems everyone cuts up a sump into fully baffled sections of 3 or 4, plus another anti-bubble trap created by using said baffles.
Is the only reason for this to protect against water level issues due to evaporation for things like a skimmer? Is that so common an issue that a sump could dry up without you noticing?

I guess as a bonus question: Why filter socks instead of a sump-wide filter sponge? They seem like an additional cost one doesn't need. Is it just convenience of removing a filter sock vs other options?

 

[JC1977]

Baffles are used for different purposes as you said some are for bubble traps or to create sections for refugiums or stable water levels for skimmers return pump chambers etc. As far as filter socks vs a sump wide sponge that’s just personal preference. Building your own sump will give you more freedom to decide over a mass produced one. I personally despise socks and have adopted floss cups on my new set up. Heck some people don’t run mechanical filtration at all. You just have to prioritize what you want in a sump and build it accordingly. In theory though you could just run an empty tank under your DT and it would work.

 

[Naekuh]

Fuge.... raise fuge level as well.

 

[strich]

Cheers. Yeah so outside of those reasons, I guess my primary confusion is that it would seem to me that flow would generally be quite poor in certain baffle configs. In particular when you have multiple baffles that overflow at the top in sequence I would imagine the flow at the bottom of the sump would be terrible, constricting whatever useful media you have in there.
Excuse my ignorance, coz I just don't have the experience, but that seems dumb to me?

Are bubble traps necessary if you don't have any overflow baffles? I assumed that bubbles are forming due to the baffles (or skimmer I guess?).

 

[DIYreefer]

I've run sumps with no baffles in the past and don't recall ever having any issues with the tanks. Just use a sump that is long rather than tall. That way the bubbles will break prior to getting to the return pump.

 

[DIYreefer]

Cheers. Yeah so outside of those reasons, I guess my primary confusion is that it would seem to me that flow would generally be quite poor in certain baffle configs. In particular when you have multiple baffles that overflow at the top in sequence I would imagine the flow at the bottom of the sump would be terrible, constricting whatever useful media you have in there.
Excuse my ignorance, coz I just don't have the experience, but that seems dumb to me?

Are bubble traps necessary if you don't have any overflow baffles? I assumed that bubbles are forming due to the baffles (or skimmer I guess?).

This is debatable, but I've always preferred lower flow through the sump (more contact time with filtration).

Bubbles will form from the water entering the sump from the display, and also from the skimmer.

 

[strich]

This is debatable, but I've always preferred lower flow through the sump (more contact time with filtration).

Bubbles will form from the water entering the sump from the display, and also from the skimmer.

Thanks for the experienced insight!
I don't plan to use a skimmer so hopefully bubbles won't be a big deal and I won't need a bubble trap.
As for flow preferences - Obviously I'm inexperienced but from what I've read and taking a look at things like algae breeders a decent amount of flow is good. By decent I'm imagining the kind of constant flow you'd get by moving the whole sump without baffles.
On the other hand I'll want a refugium and I'd not want it to be stuck up against an eggcrate divider so there will need to be some kind of testing for flow to find a happy medium!