Help with refugium basics

[pistilli]

Hi, I'm getting ready to start up a new reef tank and had some questions about the basics of refugia. My plan is to have something like a 30 to 50 gallon main tank, with a sump refugium underneath in the tank stand (so maybe 20-30 gallons). I plan to use sand or crushed coral in the refugium, along with some live rock rubble piles and one kind of macroalgae (chaeto probably). I want a mandarin dragonet in the main tank so I really want the live rock rubble to help with food production.

I'd like to just use a second tank instead of a commercial sump/refugium, and was wondering about a few things. I don't particularly want to split it into sections using baffles, so I would just have a protein skimmer and heater(s) in the refugium tank instead of seperate compartments. Do I really need to worry about fast flow rates? Or bubbles (I don't plan on getting any sponges or gorgonians, if this is the fear)? (And do baffles allow the water to go fast through the whole system because they're forcing water over the top of the refugium compartment? I guess I don't really understand the baffles...) And how fast should I be pushing water through the system? If I get an overflow box rated for a high flow rate is it ok to use a lower rate instead, or will that end up being noisy? And how should I be picking a pump, since it will be lifting water several feet? I saw the charts of pumps' power at different head heights, is it ok to run them where their actual output will be significantly lower than their maximum potential output due to height?

Anyway, if you could help me out with some (or lots!) of these questions it would be a great help. I had a lot of success with a little nano reef before, but I'd really like to understand some of the stuff I'll be using on this new tank better before I go adding it. Thanks!

-Max

 

[jumpincactus]

Baffles are a great way to assist with elimating/reducing micro bubbles from entering your show tank.

The is evidence/discussions that if there are enough of them and they are allowed to continue long enough they can irritate your critters/corals.

The flow rate will depend on how much water your overflow from your main tank feeds the sump. You will want a return pump that will keep up with the flow from the overflow. Otherwise you will have a flood. As you mentioned you will want a pump rated to push the water back up to your main tank. There are pumps available that you can get that will give you the power and head pressure to push the height you need. I would suggest a pump that is a tad overated for the head you need and you can always throttle it back to keep the sump height constant minus your evaporative levels.

There are others here that are more knowledgable when it comes to the plumbing part of this hobby.

Just my 2 cents

 

[Snowboarda42]

sorry to burst your bubble too dude, but unless you wait at least 8 months to get a mandarin, its gonna die from starvation due to no pods

 

[mr_X]

it's not true that the flow rate depends on your overflow. it depends on your return pump. how can your overflow, overflow, if the water level is not high enough to overflow into it?
your return pump feeds the display, and your overflow sends it back down.
on our bedroom tank, i have a 600 gph overflow and a 400 gallon return pump. i have no trouble with an overflowing sump.

as for the sump with refugium issue, you'll need baffles because you need to separate the macroalgae and sand /rock from the skimmer and return pump- otherwise, eventually, you'll be sucking up sand and macros will clog your pump. it will end up being a mess.
the micro-bubbles are unsightly as well.
also, your evaporation will take place in your sump. it's best to have baffles to separate your last return area(this is where you will see your evaporation), from the areas that hold your macros, and skimmer. i don't think you want those levels to drop.
your skimmer will not function the same with changing water levels, and you don't want your refugium running low on water either.

why don't you want to add baffles?

 

[mr_X]

btw, you can choke a pump back if it is too strong for your liking, but you can't add flow once it's wide open. i would get a mag7 atleast, and choke it down with a ball valve. i am headed to the store to pick up a mag7 today, for our 30 gallon cube with 10 gallon sump/refugium, because after the head loss, that 400 gph pump just trickles water.

and if you get a high rate flow box, it's going to sound about the same at it's full capacity, as it is with less flow.
you can slide a piece of tubing down the exhaust hose, to stop that "toilet flushing" sound.

 

[pistilli]

Thanks mr_x, I guess I didn't want baffles because it would take up a lot of space; most of the baffled refugiums always seem to have half their space taken up by the side compartments for the protein skimmer and the heater/return... Also I do understand that the rate of flow through my overflow is entirely dependent on the pump in the return of the refugium, I'm just very concerned about noise since I live in a studio apartment where the tank is in the same room as everything else

If I do end up using baffles, could someone explain the flow path that I should be shooting for? To isolate the evaporation to the return area I would have to have a baffle between the macroalgae and the return that blocks the bottom all the way to the level I would want the macroalgae/skimmer compartments to be at, right? Then to stop microbubbles I would need another baffle that goes from above that level nearly to the bottom, and right after the previous baffle?

From the skimmer compartment how would I want the water flowing? Would I want that to flow over a baffle into the macroalgae area? Or would I want it entering mid-tank range? I guess this relates to my first set of questions about flow rate through the macroalgae area: If the water flows over the top of a last high baffle from the skimmer, then over the top of a first high baffle to the return, then the quickest flow will all be moving over top of the macroalgae area. If on the other hand the flow is coming mid-height from the skimmer area then there would be quicker flow through the who macroalgae area (instead of just over it). Is this an effective and/or desireable way to increase the flow of the entire system through the skimmer and heater, while reducing it to the macroalgae area?

I guess ultimately I just need to know more about all of the functions of all of the baffles, and what is desireable as far as flow rates to different compartments

-Max

 

[mr_X]

intake, and the baffle on the other end of the refugium should be the same height. your second baffle, will have the water flowing over it into the return area, and that's what is going to cause bubbles.
you'll need to place a baffle after that, and then if you want a second series of two baffles, do so. my sump has just 3 baffles. the last in the return area sits up about 1 & 1/2 inches higher than ground level. i am not getting any bubbles like that.
as far as water entering mid-tank range...it's not important to do so. just let it flow over the first baffle.
the last compartment is important, and you'll want to space it out right.
i would measure my skimmer and make the first area as small as possible. the refugium and last compartments are the largest ideally.
remember when you make the first compartment, to leave space for your filter sock or whatever setup you'll be using. i just have a pool hose dangling in the skimmer area.

flow rates are debatable. not too fast and not too slow
i don't want to blow my macros over the baffle and all the bristleworms, pods, rock rubble and sand with it. but then again, i don't want the water stagnating in there either.
btw- for our bedroom tank (30 gallon cube with 10 gallon sump) i ended up taking a chance on a rio 2500 pump (782 gph), instead of the mag7. i hope it doesn't fail me. meanwhile the flow is pretty nice. it goes 4 feet up, and makes a turn through a scwd wavemaker, and 2 more turns before it reaches the display. i imagine it to be about 250gph or so coming out of the returns. :wink:

do a search on the word "refugium" here and you'll get some great information.
http://www.reefs.org/phpBB2/viewtopic.p ... t=refugium
:wink: