Sump Configuration - Cryptic Sump & Refugiim

[rpgraff]

I am setting up a fish/Frag system in a utility room with 2each 60g breeders with a sump for a cryptic sump, refugium and skimmer.

I was going to have the flow go from cryptic sump to Refugium to Skimmer before returning to the tanks.

The other day I was listening to the latest reef therapy session and the guest, David Lemus talked about his cryptic sump and refugium, he had them in either end of the sump, but didn’t elaborate on why.

I am trying to wrap my head around if one way is better or not and why

Any opinions?

 

[KrisReef]

The cryptic zone will grow sponges and pods and other things that can feed the corals. Putting a skimmer before this will suck up pods and goodies that the coral might have enjoyed.

Folks typically run the skimmer first to clear out wastes, and then the clean water flows to cryptic zone, and/or the refugium before the water returns to the main tank(s).

I hope this answers your question, as I understand it?

 

[rpgraff]

Thanks, that’s certainly something to think about, you are talking about something like this:

 

[exnisstech]

I don't know if it's right or wrong but this is how mine is set up. I think it might allow more pods and stuff to enter the display as the fuge and semi cryptic zone both flow into the return chamber. Sorry no CAD here.

 

[KrisReef]

Thanks, that’s certainly something to think about, you are talking about something like this:

Yessir.
The efficiency and flows of the skimmer and returns all work together to make it less than a straight forward conclusion as to what is most optimal, but the concept(s) are useful to guide a design.

Some folks want the skimmer to oxygenate the return water after it goes through the cryptic/ refuge area so they run those in reverse.

I don't know if anyone has done research to determine the "best' way to flow, but with proper water movement in the tanks the waters oxygenation will be appropriate for the purpose of the system.

 

[WheatToast]

@Subsea

 

[Subsea]

The cryptic zone will grow sponges and pods and other things that can feed the corals. Putting a skimmer before this will suck up pods and goodies that the coral might have enjoyed.

Folks typically run the skimmer first to clear out wastes, and then the clean water flows to cryptic zone, and/or the refugium before the water returns to the main tank(s).

I hope this answers your question, as I understand it?

Kudos to your post.

For me, nutrient management means recycle organics (inorganic & oranic) into live food to feed hungry mouths. Protein skimmers remove some bacteria and some POC (particulate organic carbon).
For the same reason that I don’t use skimmers, I also don’t wear socks in refugium.

Cryptic sponges consume DOC & POC and they produce energy rich detritus that feeds the microbial loop. In both cryptic refugium & lite macro algae refugium, a protein skimmer would remove live food if placed after refugium.

 

[YOYOYOReefer]

My reef sump is first skimmer compartment 10 inches then 48inch cryptic fuge then 12 inch return pump area . I want the contents of the cryptic area to reach the Display not the skimmer. the cryptic area is 24 inches of live rock and 24 inches of open Sump . and it lets a lot of detritus settle out on the bottom and pods thrive

 

[carri10]

I was going through the same thought process. For me, l looked at what I wanted each thing to do. Skimmer removes Organics. In my thinking this would not be used all the time, as recycling those Organics into coral food (e.g. bacteria) would be good. The refugium removes NO3 and PO4. The cryptic takes waste and turns it into biomass (food for higher organisms). In this way of thinking, I’d go skim (but only when I have to), then cryptic, then refugium, with an air stone before the bubble trap (to replace the air that I won’t get in due to not using skimmer all the time).
Fully aware that skimmers are used by almost everyone and that I’m not following consensus here.
Hope that helps. Just my opinion.

 

[YOYOYOReefer]

i don’t see any need for a lit refugium. In the bigpicture your display provides everything the refugium would to the system. It will only make it harder to keep things in balanceas they both burn the same fuel

 

[rpgraff]

i don’t see any need for a lit refugium. In the bigpicture your display provides everything the refugium would to the system. It will only make it harder to keep things in balanceas they both burn the same fuel

You do not see any benefit of a lit refugium for macro algae? The begs the question, other than photo synthetic algae, the question is, will a cryptic sump be a safe haven for all the same biomass, copepods and amphipods, etc.?

I suppose a refugium can also act as a jail for problematic fish and inverts, but then again I will have two 60g breeder tanks in a utility room for that. It would be simpler to just have a cryptic sump

 

[rpgraff]

Yessir.
The efficiency and flows of the skimmer and returns all work together to make it less than a straight forward conclusion as to what is most optimal, but the concept(s) are useful to guide a design.

Some folks want the skimmer to oxygenate the return water after it goes through the cryptic/ refuge area so they run those in reverse.

I don't know if anyone has done research to determine the "best' way to flow, but with proper water movement in the tanks the waters oxygenation will be appropriate for the purpose of the system.

To expand on this, what would be the best way to move the water from the cryptic sump or refugium to the return chamber with the idea of copepods, amphipods and other critters making their way to the display tank(s).

1. From the bottom
2. Or the top

 

[rpgraff]

Some folks want the skimmer to oxygenate the return water after it goes through the cryptic/ refuge area so they run those in reverse.

I had not considered what a cryptic sump might do to oxygenation of the water that flow through it. Do you think it depletes it significantly?

Also what I understand about oxygen and CO2 exchange, a skimmer will do more for reducing CO2 (assuming a low CO2 air source) than it will add O2 to the water. The best place for increasing dissolved O2 is from agitation of surface water in the sump and display tank. Is that correct?

 

[DCR]

I run a two-tank system very similar to your second option with each tank going separately to the refugium and cryptic sections. Both sections overflow to a small wet dry section with bio-balls because I wanted to maximize oxygenation. Although I can't say it is better than any other system, I have not found any major problems with it. I grow sponges on stacked egg crate in the cryptic and macro algae in the refugium. Both sections have a 3" deep sand bed to help with NO3 which runs less than 1 ppm.

 

[YOYOYOReefer]

My cryptic sump got tons of pods. I’ve ran both ways with light and dark fuges and just dark. for me just the cryptic sump by itself works best

 

[KrisReef]

I had not considered what a cryptic sump might do to oxygenation of the water that flow through it. Do you think it depletes it significantly?

Also what I understand about oxygen and CO2 exchange, a skimmer will do more for reducing CO2 (assuming a low CO2 air source) than it will add O2 to the water. The best place for increasing dissolved O2 is from agitation of surface water in the sump and display tank. Is that correct?

I don’t have data on skimmer oxygen and CO2 impacts on hand to say definitively how it works in my system or yours, but the general physics principle is that the partial pressure of gases in the atmosphere is where the levels of dissolved gases in our tanks will go towards with agitation (in a skimmer or at the surface) that mixes tank water with the atmosphere.

A cryptic zone can provide an ecosystem that strips O2, so I mentioned that as a caution flag for you to be aware of as you set up your sump. Algae with light can oxygenate the water, but at “night”, if a deep sand bed is present the sump may get low or zero O2 with no photosynthesis happening.

Tank circulation between the sump and DT, with a skimmer exchanging gasses and stripping CO2, and many other gases going in and out with the bubble turbulence is great until the electric power supply fails and the gas exchange gets shut down. Planning for the system to function across potential scenarios can avoid problems when they happen.

I have dual returns, in tank circulation pumps and try to keep the system clean enough so that if it shuts down the O2 in all areas isn’t going to kill my fishes.

I run my skimmer for O2 mostly, while some people don’t have a skimmer on their system. All this posting here is just for you to know what to look for and help you plan your setup accordingly, knowledge is power …

How you plan and build along the way is your own path and I think you will be okay seeing you are thinking about things before hand.

 

[mikst]

My cryptic sump got tons of pods. I’ve ran both ways with light and dark fuges and just dark. for me just the cryptic sump by itself works best

Hi, do you have pictures of your crypt? Thanks!