Acropola help

[recess62]

Looking for some advice on acropora color. I have a few sticks in a 90 gal total wv 120. Been set up since June. Livestock added August. I am new to sps. I have several acropora frags that have browned. I have read copious posts here to try to get an idea of why the color is bad

My water parameters

ph 7.98- 8.1 apex
Temp 78 apex
Salinity 1.025 refractometer
Nitrate 0-.5 salifert
Phosphate .03-.06 Hanna low
Ca 450
Mg 1200
Kh 8.5

I am running biopellets, a refuge with chaeto growing well, GAC in reactor. I make
My own water with RODI with tds 0. Running breefbuilder led. Ramp up to 75% blue and 35% white. I have 350 PAR at 3inches below waterline by apex PAR meter

Not sure why my color is bad. I have read that browning can be due to extra nutrients )phosphate ) or inadequate light. These parameters seem ok. I am
Banging my head against the wall. Please help before I get brain damage

 

[twilliard]

Zooxanthellae population which means the required conditions are met for cell reproduction. Now it comes down to light.
Give the coral a reason to protect that zooxanthellae.

 

[saltyfilmfolks]

start increasing light.

also if you led's native color temp is 16,000 kelvin and your ratio is 75 35 your probably running 35,ooo kelvin.

 

[recess62]

Ok I understand. So even though I am running 350 PAR I should still increase light? If I understand this I am treating based on coral health rather than an absolute PAR value

In terms of the temperature of the light. Should I be increasing my blue or white ? What ratio of B/W should I be striving for? I am a scientist so I like hard numbers hense the PAR meter. Is there an affordable way for me too measure light temperature ?

 

[dave57]

Lower kelvin lights will promote more algae growth and possibly increase coral growth, therefore increasing the temp and par will create better colors but can sacrifice growth. Also feeding corals can make the colors better. It's all a balance I believe. One fact to realize is that bright coral color doesn't mean the coral is healthy it basically means it's shielding and reflecting light. Creating pigment proteins. Decreasing your nutrients itself can create lighter or brighter colors depending on the nitrates and phosphates, also considering your alkalinity levels are in check. Also different spectrums will produce different colors.

 

[saltyfilmfolks]

Ok I understand. So even though I am running 350 PAR I should still increase light? If I understand this I am treating based on coral health rather than an absolute PAR value

In terms of the temperature of the light. Should I be increasing my blue or white ? What ratio of B/W should I be striving for? I am a scientist so I like hard numbers hense the PAR meter. Is there an affordable way for me too measure light temperature ?

no not an inexpensive way to test color that I know of unless you find a used color meter, and its a challenge to get it with leds. check your fixture, it likely that it has a "native" color temp @1:1 ratio.
You may consider just bringing up your white chanel slowly.
Many debates on color over the years. some say 20k some 14k. Our Local Guru Diesel runs 14k or LESS. with giesemann tubes.