What's the Best Contents for a Refugium?

[HL649]

I am just setting up my 1st refugium in my sump. I am wondering what is the best stuff to put in there? I will probably get some Chaeto growing but was wondering what is better - rock rubble, sand substrate, crushed coral...

Thanks.

[daniella3d]

I would go with micro algae instead of cheato as cheato I have read takes a lot of calcium from the water. I like the caulerpa prolifera the most as it grow incredibly fast and can be served to vegetarian fish as food. Especialy tangs like that stuff.

It will remove a lot more nitrates from the water because it is growing so much faster than cheato. A bit of cheato is ok for giving a refuge to pods but the micro-algae like the caulerpa is much more useful. I have also the caulerpa that looks like a feather and I can sell that stuff so quickly and make money with it as it too grow fast.

I am just setting up my 1st refugium in my sump. I am wondering what is the best stuff to put in there? I will probably get some Chaeto growing but was wondering what is better - rock rubble, sand substrate, crushed coral...

Thanks.

[blacknife]

I don't know the answer but I do know it depends on what you plan to do with the refuge-um, Nutrient reduction, pod factory or what not.

[mark]

use Chaeto in a 20g BB fuge with LR. Lots of pod in the Chaeto, don't have a problem with Ca but am running a reactor anyways. Thinking the stuff must be also be good for nutrient export as can go from a grapefruit to basketball sized ball in 3-4 weeks.

[viperfish]

I would go with micro algae instead of cheato as cheato I have read takes a lot of calcium from the water.

Please share the source where you read this. There are some calcareous forms of macro algae such as Halimeda, Rhipocephalus and Penicillus but chaetomorpha is not in this group.

It will remove a lot more nitrates from the water because it is growing so much faster than cheato. A bit of cheato is ok for giving a refuge to pods but the micro-algae like the caulerpa is much more useful.

I think this is a matter of opinion and not fact. They are both excellent at exporting nutrients, they just behave differently and therefore one may outgrow the other depending on the type of refugium setup.

[HL649]

I have read that Caulerpa can cause problems if it is allowed to go sexual, is this a real problem? I am looking for something that is idiot proof (at least as idiot proof as you can get with a SW tank).

I am leaning towards using a rock rubble base with a ball of Chaeto. My main goals are for nutrient export and a home for pods.

[whatcaneyedo]

In Reef Invertebrates by Calfo there is a lengthy section outlining the pros and cons of caulerpa. Some of the cons are that it can go sexual where the whole colony suddenly dies and begins to decompose polluting your system. It also appears to yellow the water and release calcifying inhibiting compounds that stunt the growth of stony corals. However these problems can be combated by leaving your refugium lights on 24/7 to prevent going sexual and running activated carbon to keep your water clear. One of the other issues that I have with caulerpa is that it can be very invasive. If a small amount somehow makes it into your display tank and gets established it is often difficult to remove. Caulerpa has little hold-fasts that cling to rockwork making manual removal very long and tedious. Also, its sort of hit and miss as to whether or not fish will eat it. In my experience most tangs prefer other foods.

I personally like gracillaria and chaetomorphia. They don't grow as well as caulerpa for me but they grow well enough. They also aren't nearly as invasive or problematic. I grow both in my frag system without any issues of them clinging to everything. The right species of gracillaria is suppose to be very palatable for tangs.

[daniella3d]

It will cloud the water but the coral seem to like it. I have yet to see my caulerpa prolifera go sexual and do I wish it would because I made the mistake of putting this in my display and it's very prolific! So far after a year it has never gone sexual. Once a caulerpa go sexual it melt away but produce spores that can sprout new plant. I never managed to get new plant from this though, so it seem that the spores are probably being eated.

The caulerpa that looks like a feather does go sexual in my main tank about once or twice per year and when it happen it is by batch. Not all the caulerpa goes sexual at the same time. Then the water become a little cloudy and that is removed by the skimmer in a few hours. My corals always open wide when this happen as they seem to enjoy eating the spores.

It has no effect on fish that I can see.

The caulerpa prolifera seem to never go sexual and it is the best for a refugium because it grow so much faster than the cheato. I would do 2 sections, one with cheato for pods and one with caulerpa prolifera. Tangs love to eat this algea and it is very good for them to do so.

I have a blue hippo tang and a niger triggerfish (both very messy and piggy eaters) in my 75 gallons and always zero nitrates :) I have only a Deltec 300 that is running during the day and I shut it down at night. So far after 3 months of feeding them 3 to 4 times per day, still zero nitrates. I have loads of caulerpa in my display tank as I do not have a refugium.

Also choose your liverock wisely because some like the Totoka will export a lot of nitrates as well. A porous rock will filter nitrates out (anaerobic bacterias deep inside porous liverock) as I have this in my aquarium and I beleive that the caulerpa mixed with the Totoka is the key to the zero nitrates in my aquarium.

And last but not least, if you still have a problem with nitrates, then adding a reactor and biopellets will do the job. Must be started very slowly as this can do a bacteria bloom and take all the oxygen in the water and kill the fish.


I have read that Caulerpa can cause problems if it is allowed to go sexual, is this a real problem? I am looking for something that is idiot proof (at least as idiot proof as you can get with a SW tank).

I am leaning towards using a rock rubble base with a ball of Chaeto. My main goals are for nutrient export and a home for pods.