Can Seagrass be used as nutrient export in a sps dominate tank?

[ADHybrid]

Ok guys, I have a question that I'm hoping someone has experience/knowledge of so they can help me out. I am in the process of setting up a 140 gallon aquarium and plumbed with it will be a 100 gallon refugium. I asked my parents about drilling through the wall so I can place my sump/refigum in a room where It cant be seen and they pretty much smashed that idea, so the sump will be under the stand and the refugium will have to be next to the tank. I'm dreading having my refugium next to the aquarium displayed so I'm thinking of perhaps making something more of a "displaygium' or a display refugium. I was thinking I could use seagrass as my main nutrient exporting plant but then I was thinking it over and realized that since this tank is going to be mostly sps dominate, I will be striving for near zero nutrients and I fear that my skimmer (thinking of building a 4 foot tall skimmer for this bad boy) will out compete the grass for nutrients and kill it off. So here are my questions.


1. Is having a seagrass refugium plumbed with a sucessfull sps tank even a viable option?

2. If so, what is the best way to make this work out?

3. If not, any other suggestions for a display type refugium that can work with sps?

4. Also, if this will work, which type of sea grass would you use and where is the best place to buy this stuff (I'm having a hard time finding it)

Thanks in advanced guys.

-Chris

 

[Paul B]

In the summer I collect this stuff, I don't know if you can get it in your area, I put it in my tank but the fish eat it, in a refugium it would be better. I also use codium but the snails eat it.
Paul

 

[piercho]

Seagrass is not useful for significant export, IME. I would not consider it a viable option. My seagrass does, however, survive under very lean water conditions because it gets its fuel from the filthy sandbed. So I don't think that the skimmer is a consideration. Of the seagrass I've tried, Manatee grass produces the most mass in its blades and I do occasionally chop it off at substrate level. But compared to my algae scrubber, the amount of export from the grass is trivial.

Several algae do well and grow fast in a high-flow sump. Chaeto is the current craze, but IME its not the most efficient and its certainly not the easiest. Since I installed my algae scrubber its died out entirely. Inland Aquatics on the web sells a 5-algae kit for stocking refugia, they use to ship it in un-insulated tubes in the summer for not too much money on shipping. An algae tank can be just beautiful, certainly as nice as a grass tank.

The main thing, IMO, in your design criteria is to put a high rate of flow through the refuge and light it intensely. You want the refuge to be a better environment for algae growth than the display tank and that means high flow and high light. That is, if you decide to attach an algae filter to an SPS tank, and many people don't and you can certainly have an SPS tank without one.

 

[piercho]

On sources for seagrass, try the links to sites that sell plants at the top of the Marine Plants Forum. I got Turtle, Manatee, and Shoal from Florida Pets. The address for Inland Aquatics is also there, and I'd try their refugia flora kit for macros. If you are in a reef club, try the members. When I use to have a lot of the macros I use to have a LOT of the macros, and I gave away quarts and threw away gallons of the stuff.

 

[ADHybrid]

Paul B,
Thanks for the reply. Unfortunetly, nothing that grows in my area is suitable for a tropical marine environment.

piercho,

Thanks for the reply. I think that I'd get tired of just seeing a huge mass fo cheato sitting in a 100 gallon refugium therefore I dont want that to be my SOLE sorce of vegetive filtration. I'd like to stay away from any type of caulerpa since they can give off noxious chemicals that have been found to stunt sps growth so I guess I'm kinda running out of options. My main idea with sea grass was I could keep a 'lagoon' type system with sea horses and pipefish in the refugium with some cheato, sea grass, and other types of algae (if I can find some good ones) that aren't detrimental to sps. Basically, my skimmer (which I plan on building oversized) will be the bulk of my filtration, and my refugium is bind any excess nutrients that my skimmer didn't get. Any suggestions on other algae besides caulerpa that will take up nutrients, grows rather quickly, and doesn't give off noxious chems? I was thinking maybe like sea lettuce (ulva genus) but after that I'm running out of options. Thanks again guys.

-Chris

 

[Bearbait]

Thats called turtle weed this is whats called Sea Grass

 

[Samala]

Turtle weed (Chlorodesmis sp) and Turtle grass (Thalassia testudinum) are two different things. Ones a small thick macro.. the other a long, bladelike, true marine plant. I dont think you have turtle weed actually.. though its hard to tell if you've got turtle grass or not. Looks to be mixed in with a macro w/ a branching rhizome/stalk.

Its a good lookin tank though! And I love love love your SH girls! Some really pretty spots on the one, never seen that before.

>Sarah

 

[piercho]

Eric Borneman runs an SPS tank plumbed with an adjacent seagrass tank. He no longer visits his own forum(???) but if you search diligently through the Coral forum, there are threads where he talks about and shows pictures of his setup. I keep a DSB in my stony coral tank, so do some others (check out JB NY and his tank).

The trend over the last 2 years has been away from sandbeds for SPS tanks and back towards a more modern version of the Berlin system. Having a large nutrient buffer, like a DSB, adjacent to (or in) a SPS tank has been a subject lengthily and sometimes heatedly discussed through the forums. A marine biologist under the board name "Bomber" tends to dominate the discussion these days on RC, and he is very adverse to the idea that there is any benifit to having a DSB for SPS. I don't agree with all of his conclusions, but one thing has become abundantly clear to me: you don't need a DSB to manage a low-nutrient tank and it may be easier to manage a dedicated SPS tank without one. So I just thought that I'd throw that out there if you are putting a DSB in the sump for the benefit of SPS coral. Do a search for "Starboard Reef" in the general forum started by Bomber if you are interested in his opinions.

Conversely, if you intend to achieve very low nutrient levels through use of a vegetative filter, my experience experimenting with 4 different setups over the last 4 years is that the algae scrubber described by Adey in the book "Dynamic Aquaria" works best. A low-flow refugia with macro that does not recieve a significant portion of the tank's turnover works for crap for nutrient control, IME. But a high-flow, brightly-lit sump with macroalgae works fairly well, IME, just not as good as a scrubber. And both the high flow and low flow refugia have a major advantage of a continuously recharging your tank with microfauna.

There are many non-caulerpa macros available out there. As your nutrient levels change over time, the most competetive ones for that condition tend to dominate. I would try the Inland Aquatic Refugia Flora Kit to get a variety of algae and try to keep all specie going as long as possible. That gives a variety of refugia algae that have worked well for Inland, and they've got more years of experience maintaining refugia than most people. Also, check out their algae list in their product section. They have dozens of different plants available on a periodic basis.

I would not worry about having a bit of Caulerpa in mixed-genus vegetative filter. I've found one, Caulerpa racemosa var. peltata, to be quite competetive at low nutrient levels in the tank. One of my strategies with real pest algae like Asparagopsis and C. var peltata is to put them in my vegetative filter. The rational is that in the better growth environment in the filter, they will out-compete the same plants in the tank. Its counter-intuitive, but it seems to work. I think the backlash against Caulerpa is because 1) its escaped into the wild from cultivation and become an invasive nuisance 2) vegetative filters with a large biomass of caulerpa may leak enough caulerpins to inhibit coral growth and pose the continual risk of "overgrowing" thier nutrient source and releasing all those nutrients back during massive sexual reproduction events.