What signs would indicate Light % too low???

steallife904 · Jan 29, 2019

Just had a question pop in my head, what signs would one see that could possibly indicate your lights are to low or not enough power? I run LEDs (reefbreeder photon V2) and have the channels pretty low compared to what I have seen others do on these lights and other LEDS. My blues max are 50ish and whites under 20. I now only have LPS and for the most part most are good. I have a couple though that just haven't looked great or slightly receded. My ALK has been steady at 8dkh, Calc 440 and mag around 1400. I do believe my nitrate and phos are low but working on that. Just thought though maybe the lights need to start bumping up some??? If light is to high I no you can burn the tops and bleach but what about lighting to low?

RobZilla04 · Jan 29, 2019

Do you have any zoas or softies that appear to be "stretching" for light? Usually if you have one or two on the bottom/middle they can give a good indication that light intensity is too low.

Coupled with increased light intensity, consider increased flow and possibly nutrients. Coral food, aminos, etc can be easily supplemented in light doses when N & P export becomes very efficient.

jda · Jan 29, 2019

Yup. Super high polyps extension or corals extending their "stalks" to get higher. Z&P that are usually the size of pencil eraser heads becoming larger like dimes or nickel size. Clams open as wide as possible almost wanting to pull themselves apart. This is harder with SPS where growth can be slower and the colors can be out of whack - sometimes lighter (mostly) but also some get darker.

steallife904 · Jan 29, 2019

no zoas or softies for me. 100% LPS right now. I do target feed once a week. Not sure if the LPS would give me a clear sign they want more light???

jda · Jan 29, 2019

Chalices, acans and those types can really extend and get puffy if they want more light. Harder to tell with euphillyia since they are supposed to be out and extended.

nereefpat · Jan 29, 2019

How is the growth?

In general, too high of light (especially with low nutrients) can cause bleaching, where too little light can make corals turn brown.

gtrider · Jan 29, 2019

Have you measured PAR in the tank? I rented a meter and mapped out my PAR as it pertains to my current LED intensity. It gave me an understanding of light intensity around the tank. With that information, i'm not able to place coral in locations that suite their requirements.

Instigate · Jan 29, 2019

You could always grab a cheap lux meter to get a rough idea of where you're at.
https://www.reef2reef.com/threads/new-lux-meter-how-do-i-use.368945/#post-4549549

vetteguy53081 · Jan 29, 2019

Puffiness, retraction of polyps or feeders, zoas closed up and very dim in the lens of a camera or phone- some indicators

steallife904 · Jan 31, 2019

The growth I would say is slow, but most I am looking at are 5 or 6 month old acan, blasto, favia, torch and frogspawn frags with 2-6 heads. Couple acans and favia and chalice are my ones that receded some and don't look as happy. Have moved them all over with not much change.

Never used a par meter. How much is a cheap one? Or rent?

jtl · Jan 31, 2019

I don't think your RB settings are too low. Mine are 45% blue and 20% white at the peak and if you plug the numbers into the RB speadsheet that is Par from about 300 at the top to 100+ on the bottom of a 20" deep tank. BRS and WWC claim Par between 225 and 300 is good for sps and under 100 for lps. They can likely take higher numbers but this appears to be a safe temp for pouridge (not too hot and not too cold).