Is this enough light for Acropora?

[chcgregg]

I have two Reef Flare bar lights 90cm long paired with a 4x39w T5 fixture (2x blue plus, 2x coral plus).

The reef flares are on for 12 hours at 100%, and the T5 on for 12 hours also. The lights are mounded 20cm above the water line, and all Acropora are growing 40cm deep from the water line. So the lights are mounted 60cm above the Acropora.

Some of the Acropora are paling in colour, where as some are looking okay. Growth is slow. Nutrients are 10pm nitrate and 0.03ppm phos. 11 Chromis and one two spot bristletooth. Alk is at 7.7dkh and calcium 425ppm. Coralline everywhere.

I don’t have a par meter, but based on others experience is this enough light? Could I me over doing it? Any suggestions?

Cheers,

 

[T-J]

Any suggestions?

Yes, rent/borrow a PAR meter. That's the only way you will really know what your numbers are throughout your tank.
Also, you didn't mention what size tank this is.

 

[bradreef]

T5s have grown acro for 20 years. 4 t5s can slowly grow much of the sps coral. 8 bulbs should grow really well. Do you have 2 4 bulb fixtures or two fixtures totaling 4 bulbs?

 

[bobnicaragua]

How about a picture?

 

[Troylee]

Sounds like it’s bleaching if They’re getting pale.. or low nutrients

 

[chcgregg]

T5s have grown acro for 20 years. 4 t5s can slowly grow much of the sps coral. 8 bulbs should grow really well. Do you have 2 4 bulb fixtures or two fixtures totaling 4 bulbs?

Only one fixture with 4 bulbs and two reef flare either side.
Apparently the reef flare output 300par at 40cm deep, which seems plenty for Acropora growth, paired with the 4 T5, I could imagine I could be over doing it.

 

[chcgregg]

Sounds like it’s bleaching if They’re getting pale.. or low nutrients

The amount of food I’m feeding per day to keep 11 chromis happy certainly wouldn’t meet the criteria for a low nutrient system, plus nitrates are at 10ppm.

 

[chcgregg]

Yes, rent/borrow a PAR meter. That's the only way you will really know what your numbers are throughout your tank.
Also, you didn't mention what size tank this is.

Probably.

90x35x40cm.

 

[T-J]

Probably.

90x35x40cm.

Like stated above, T5s have been used for a loooong time (had some over one of my tanks ages ago with MH's).
You "shouldn't" have issues with that sized tank, but you could be bleaching them as well.
Can you join a local reefing club and see if they have a PAR meter you can use?

 

[chcgregg]

Like stated above, T5s have been used for a loooong time (had some over one of my tanks ages ago with MH's).
You "shouldn't" have issues with that sized tank, but you could be bleaching them as well.
Can you join a local reefing club and see if they have a PAR meter you can use?

I have a feeling the reef flares are much more powerful than they appear. the tank doesn’t look bright, I’ve had plenty others with halides and 6x T5 with no issues, but it could be the reef flares.

I could try, not much around here in South Australia. I probably will invest in a seneye

 

[Christian0505]

It’s probably your low po4 which causes the paling, but like said, rent a parmeter. I doubt it’s too much light. I run the same t5 bulbs on my 90cm with 2 radion XR30 g5 blue. I have acro’s right below the water surface that do not bleach.

 

[T-J]

I have a feeling the reef flares are much more powerful than they appear. the tank doesn’t look bright, I’ve had plenty others with halides and 6x T5 with no issues, but it could be the reef flares.

I could try, not much around here in South Australia. I probably will invest in a seneye

I used a Seneye before I had access to an Apogee PAR meter. The results were really close to each other (LED Lighting).
Here's my review of the Seneye:

 

[chcgregg]

It’s probably your low po4 which causes the paling, but like said, rent a parmeter. I doubt it’s too much light. I run the same t5 bulbs on my 90cm with 2 radion XR30 g5 blue. I have acro’s right below the water surface that do not bleach.

Even at 0.03? What phos numbers are you keeping?
What intensity are your radions running at and how long is the photo period?

 

[Christian0505]

Even at 0.03? What phos numbers are you keeping?
What intensity are your radions running at and how long is the photo period?

Well I’ve multiple reason to run higher phosphates as I run a mixed reef with mant lps. Do you run sps dominant?
I run my phosphates preferably at 0.08-0.1 ppm. As I think this colours up my acro’s to a nice rich colour instead of the light pales. But than again, my goniopora and other lps like it as well in that range.
it also depends on which acroporas you have. Tenuis and millepora for example prefer the phosphates abit higher in my experience (0.07-0.1) where as the microclados would do extremely well in your 0.03 ppm of phoshaTes

i run the radions at 39% intensity, all spectrum 100%, which equal the AB+ programm on the radion XR30 pro’s at about 46% intensity.

radions run from 11 am to 9 pm at full power, with 1 hour ramp up starting at 10 am and 1,5 ramp down endint at 10:30 pm.
T5 run for about 5 hours from 1

I have a waterbox peninsula 3620, and running at arround 220 par on the sandbed and arround 450-470 just beneath the watersurface.
I’ll try to get a picture later tonight.

I think it is important you realise the relationship between light, flow and nutrients and therefore the importance of renting a parmeter.

to my knowledge/experience there is no “right” number of nutrients. I always look at it like this. If you blast your corals with light and flow, they have “less” time to absorb nutrients, and they become the limiting factor, by increasing the nutrients they can absorb “more” in the “less” time they have.

So in your situation (assume your par output is as high as you think), you could do two things to improve the colour of your corals, either increase po4 or decrease your lightning. Eventually both will create the same end results, expect by increasing your PO4 you might get some more growth out of your corals.

Please be carefull with using my explantion as it is based purely on assumption, so please meausure your par and provide us more details about your tank/coral. Pictures could also help.

 

[findingsimple]

I have a feeling the reef flares are much more powerful than they appear. the tank doesn’t look bright, I’ve had plenty others with halides and 6x T5 with no issues, but it could be the reef flares.

I could try, not much around here in South Australia. I probably will invest in a seneye

Whereabouts in SA? I know a place that rents out a PAR meter

 

[chcgregg]

Well I’ve multiple reason to run higher phosphates as I run a mixed reef with mant lps. Do you run sps dominant?
I run my phosphates preferably at 0.08-0.1 ppm. As I think this colours up my acro’s to a nice rich colour instead of the light pales. But than again, my goniopora and other lps like it as well in that range.
it also depends on which acroporas you have. Tenuis and millepora for example prefer the phosphates abit higher in my experience (0.07-0.1) where as the microclados would do extremely well in your 0.03 ppm of phoshaTes

i run the radions at 39% intensity, all spectrum 100%, which equal the AB+ programm on the radion XR30 pro’s at about 46% intensity.

radions run from 11 am to 9 pm at full power, with 1 hour ramp up starting at 10 am and 1,5 ramp down endint at 10:30 pm.
T5 run for about 5 hours from 1

I have a waterbox peninsula 3620, and running at arround 220 par on the sandbed and arround 450-470 just beneath the watersurface.
I’ll try to get a picture later tonight.

I think it is important you realise the relationship between light, flow and nutrients and therefore the importance of renting a parmeter.

to my knowledge/experience there is no “right” number of nutrients. I always look at it like this. If you blast your corals with light and flow, they have “less” time to absorb nutrients, and they become the limiting factor, by increasing the nutrients they can absorb “more” in the “less” time they have.

So in your situation (assume your par output is as high as you think), you could do two things to improve the colour of your corals, either increase po4 or decrease your lightning. Eventually both will create the same end results, expect by increasing your PO4 you might get some more growth out of your corals.

Please be carefull with using my explantion as it is based purely on assumption, so please meausure your par and provide us more details about your tank/coral. Pictures could also help.

plenty of flow, but I agree the system is phosphate limited. Funny that haha. Added 6 more chromis three weeks ago to total 11 and the phosphate drops! Refugium must be doing a very good job at keeping the nutrients low.

Time to start feeding even more!

 

[chcgregg]

I know a place that rents out a PAR meter

I know of a couple places which do, but I’ll look at a getting a seneye.

 

[Christian0505]

As promised an indication of how my acroporas are positioned.

 

[Christian0505]

plenty of flow, but I agree the system is phosphate limited. Funny that haha. Added 6 more chromis three weeks ago to total 11 and the phosphate drops! Refugium must be doing a very good job at keeping the nutrients low.

Time to start feeding even more!

I have 15 fish in my system and still need to dose Red Sea AB+ and reefroids to keep up the nutrients haha, once you get your corals really growing the tank depletes like crazy. But high input, high export is my way to go