gracilaria question for you algae masters

[naterealbig]

Hey kids,

I have a 60gal with a 20gal fuge. The fuge is seperated into three chambers, with LR and macro in the middle. I have (what seems to be several species of) chaetomorpha and (one species of) gracilaria. Sitting on top of this 16" deep middle section is a 96watt 65k coralife PC light. The algae is growing, both the gracilaria and the chaeto, but they seem to be bleaching. The original bunch of chaeto is much greener than the new growth (older is dark dark green and new is almost neon in color), and the gracilaria's new growth is almost white, and the original clump is getting lighter and lighter. I don't understand, because my common sense is telling me that the 'bleaching is bad, but there is visible new growth from both macros. Any ideas? Thanks for your help.

 

[mano]

I've had cultures of Gracilaria turn white at the tips during high temps and also increased salinity. Had any of those changes recently? Can you get a pic?

Christine

 

[naterealbig]

Well, I run a pretty consistent temperature (81+-1 F) and my salinity is at a constant 1.025. I dropped my camera a couple of weeks ago and don't have a replacement yet. I'll try to borrow my friends and post a pic as soon as I can. I was originally thinking that maybe the 96W pc was 'burning' it, but I don't know if thats possible......this is my first refugium.

 

[graveyardworm]

How long has the fuge been set up, how long has that lighting been on there, and how long have you had the macros? Bleaching may be a sign of low nutrients, can you post any parameters, and are you currently dosing anything? The gracillaria tends to prefer lower lighting than the cheato, so the lighting may also be the cause of bleaching with the gracillaria.

 

[mastou]

<a href=showthread.php?s=&postid=8641353#post8641353 target=_blank>Originally posted</a> by graveyardworm
The gracillaria tends to prefer lower lighting than the cheato, so the lighting may also be the cause of bleaching with the gracillaria.

That is also my experience, I had some Gracilaria growing under 150W HQI and it turned almost bright yellow, where as the Gracilaria growing in the shadow was reddish-brown. Both seemed to grow but it the Gracilaria in the shadow grew more that directly under 150W.

/Magnus

 

[naterealbig]

How long has the fuge been set up, how long has that lighting been on there, and how long have you had the macros? Bleaching may be a sign of low nutrients, can you post any parameters, and are you currently dosing anything? The gracillaria tends to prefer lower lighting than the cheato, so the lighting may also be the cause of bleaching with the gracillaria.

Refugium Age: About 6 months

Length of Light: I had a 18 watt flourescent for about 4 months, on the fuge and only one of those months has it had the macros underneath. Neither of them showed any growth during this time. About 2 months ago I purchased the 96watt 20" PC from coralife. That is when the macros started 'bleaching', but they also started growing like crazy. As I said before, the chaeto is just a lighter brighter green, but the gracilaria is almost white in the outer areas (darker towards the middle-but not nearly as dark as it was originally)

Parameters:
NO3 - 0
PO4 - 0
Mg - 1200
Ca - 410
Alk - 9.8
pH - 8.3

Dosing: I dose calcium, magnesium, and alkalinity buffer to maintain specified levels. I also add 1 tbsp DT's phyto twice a week.

Inhabitants -

1 med Blue Damsel
1 med maroon clown
1 large long tentacle anemone
1 sm acropora
1 sm millipora
1 sm birdsnest coral
1 sm (3in) T. derasa

Equipment - see descriptionCurrent Tank description below.

 

[naterealbig]

noteworthy? I keep the light about 3" from the top of the refugium's water.

 

[TekCat]

So, anyone knows the "proper" environment to keep gracillaria?

 

[hyperfocal]

http://www.sms.si.edu/irLspec/Gracil_tikvah.htm suggests that a reduced level of light is beneficial for Gracilaria sps. Not sure exactly what that is reduced from, or how that translates into wattage.

I guess less is more?