[SupaJSK]

What does Caulpera look like when it goes sexual? And what does that mean for a tank when it does? How does one prevent it?

I recently had all the caulpera algae in my refugium die off. My nitrates are still high, which is the reason why I started the refugium in the first place.

I have tons of rock and about 4 or 5 inches of sand in my main 100 G tank. The refugium is about 30 gallons and has rock and sand too with a 32 Watt PC light over it 24 hours a day. One thing to note is that the main tank still has the undergravel under the sand. Something left over from the original setup when I took it over and converted it over from fish only to reef. Could that be causing any problems? Its totally covered with sand.

Nothing has really changed in my tank recently. All my corals and animals are doing fine. Not growing like I'd like to though.

Any help? Thanks guys.

[scubadude]

Calerpa going sexual usual means that the little grapes release toxins and get white or greenish/white, this usually happens because you dont have enough light or you are not harvesting the calerpa enough. If you had the calerpa die off then you need to get the parts that are dead out and probably do a w/c or two and keep your skimmer cleaned....wouldnt hurt to throw some carbon in the flowstream as well. Are you saying that you have an Undergravel filter still hooked up? Dude if so you really need to slowly do away with that...Do you have powerheads still hooked to the lift tubes? If so I would definately turn them off....maybe one first...and do a water change....then after a week turn another off then do a w/c...just do a slow graduation to removing the U/G filter...dont try and do it all at once.

[SupaJSK]

actually just the trays are under the sand. no tubes or powerheads.

[adamgrandprix]

so what you really have then is a plenum... not a UGF
I wouldn't worry about it at all.

[SupaJSK]

A plenum?? Thats what its called!? LOL! When I first started the tank two years ago, my LFS put it there and I've never pulled it out. What exactly is it supposed to do anyways?

What reasons would there be for all of my caulpera to die off so quickly? When I first added it, it grew like crazy, now i barely have any left.

[scubadude]

Originally posted by SupaJSK

A plenum?? Thats what its called!? LOL! When I first started the tank two years ago, my LFS put it there and I've never pulled it out. What exactly is it supposed to do anyways?

Some people use plenums still, and I think they will work but most ppl have converted to DSB's and sand w/ the u/g filter (plenum) is really not effecient, because the grain size of the sand generally will fall through the grate thus defeating the purpose of a U/G filter. I personally have no interest in plenums anymore. Except maybe for a freshwater tank. But you really should use one or the other not both...As long as your pumps arent on the lift tubes you are ok...I personally would cap off the lift tubes after I did a water change and Siphoned all the crap buildup through the lift tubes...I think I might even fill them with sand so as to not leech detritus and buildup from underneath the U/G grate.

Originally posted by SupaJSK

What reasons would there be for all of my caulpera to die off so quickly? When I first added it, it grew like crazy, now i barely have any left.

Flow? lighting? Nutrient Competition? Harvesting? Could be many reasons....not exactly sure... Calerpa isnt the most stable macro algae to use, everyone likes using it because its the most readily available and its a fast grower, and easy to just rip out as it grows. Im not saying you should totally do away with it, but the more types of macro algae you have in your system the more stable it will be IMO. Do you have other algeas that are growing in your tank? Like cyano? if you do and you have a bunch of cyano then more than likely the cyano will be pulling all the nutrients out of the tank thus not leaving any food for the calerpa....in this case you have to manually remove all the cyano and put as much healthy calerpa (or other macro) in there to out compete the cyano. Its like a race to see who wins.

[SupaJSK]

thanks for the great info. i guess i should remove the plenum. it cant really cause anything bad right?

i dont have any cyano in my tank. luckily ive never had to deal with it in this tank. in my 20 gallon i have. i have the light on 24 hours in my refugium (should i be on 24hrs?), and the water flows through the refugium before getting to the second sump which houses the skimmer. anything else i might try? thanks again.

[scubadude]

I would try going w/reverse photoperiod on your refugium....so that when the main tank lights are on the refugium lights are off, and vice versa. That may help stabilizeing your macros....it will definately stabilize the PH more. As far as your plenum goes I wouldnt be too worried about removeing....just make sure that the uptubes are unhooked and try to cap them too. You could just shove some chunks of liverocks down in there if u have to. If you ever redo the tank you may want to take it out but I dont think its vital.