Input on sump design needed...

[Pennyworth]

I have the following tank setup:

So water is returned from the right sump to the tank, and via an overflow is returned to both sumps.

The sump on the left has crushed up and some solid live rock, and I would eventually like to use it as a refugium.

I'm a bout to add a protein skimmer to the tank on the right, and have found a few models that will fit nicely and are rated for about twice my tank size.

My concern is that any pods in the left sump will get sucked up and skimmed and won't be able to make it to the return pump, and thus to the main tank.

Is this a legitimate concern or not something to worry about? If it is a legitimate concern, do I have other options?

Should I take all the LR out of the left sump and have it in with the return pump, and have the skimmer in the left sump?

 

[DWhatley]

Not having set up a sump this way I can't offer knowledgeable advice but I would think that if you are planning on a refugium, you would want as much hardware as possible on the left with the fuge (LR, pods, macro algae, lighting and return pump) on the right for space. Since your flow is left to right, this would keep not only pods but macro algae and anything else you place in the fuge away from the skimmer pump. However, for maintenance (removing the filter sock and cleaning the collection cup) I suspect placing the skimmer on the right would make things easier (or not depending on the difficulty of getting to the filter material on the right).

 

[Pennyworth]

I have been researching the last few hours but haven't really found much. It does indeed seem the best way is to swap the LR into the right sump and keep the return pump there and have that as the refugium, while having the skimmer on the left.

That way anything bad is skimmed, but only pods that are coming back from the main tank will be trapped.

I've found a compact skimmer that would fit in my sump with room to spare.

Is there any down side to this setup?

Do I have to worry about crushed live rock getting sucked up by the return pump?

 

[DWhatley]

There should be no problem with live rock unless it is very small (like sand). If you want a sand bottom (I don't recommend it) in the fuge then you will want to put a filter sponge over the return pump intake. This will not allow a return of the pods but I don't know how well they would return anyway as they would have to survive the impeller. I am not sure how well macro algae would do with the return pump unshielded. You may want to consider a baffle (acrylic plate shorter than the sump sides) placed between the return pump and the rest of the fuge. Most refugiums that are set up for returning food automatically are place above the display and use a pumpless return like a cascade filter arrangement where the water is pumped up to a hang on tank and then returns by gravity but this is not something you can realistically do for an octopus tank.

Your pods coming from the main tank will be (mostly) alive and well in your filter sock and can be collected and returned to the aquarium when you clean the sock (I clean mine once a week to once every other week depending on how blocked they have become). You will want to flip your sock inside out over a collection area and have a small cup of tank water to place them in as you pick them off . They are pretty hardy. I typically collect them from all the tanks at once and add them back to which ever tank seems to need them and think this may add a bit of genetic diversity but I don't know that there is any real benefit.

 

[Pennyworth]

My only concern was to have a pod population in the refugium and that these would not make it to the main tank.

But if I can just have the pod population in the main tank, then I don't really have a problem.

I guess the main point of the refugium is plants to deal with nitrates. In which case I guess I can leave things how they are, and place the skimmer on the right side along with the return pump.

Sorry for thinking outloud here...but it's late, and your input actually helps a lot

I actually don't have any pods at the moment, getting some from my LFS tomorrow...it will be the first life in my tank :>

If I can leave things as they are, that gives me roughly an area of 9, maybe 10" by 8" on the right. Height isn't an issue, and I've found a few sumps that will seemingly fit in there.

A Reef Octopus NWB110, A Reef Octopus 110 space saver(!) both rated for 110 gallons and a CoralLife super skimmer needle wheel rated for 125 gallons.

Would you (or anyone else) have any input on if one is clearly better than the others and why? I've been reading the Corallife uses bigger bubbles so may be slightly less effective, but I'm not sure.