Average par for growing SPS

[Biff0rz]

slimer

5/31/23

I dont have a side view of it because #slimer but it's about 15" tall now, maybe a bit taller.
4/23/26

That's 'fast' but honestly, its still kinda slow.

200 par at the bottom, now getting 350+ at its top

 

[reef’r]

both are subjective to a point. If they have color, new lights likely wont help. If they are brown, then sure.

Sps grow slow. How are you judging the speed? I have a few that grow fast, but, its still slow.

Sorry I feel like I missed something...... So you are changing over to metal halides? Did you just recently change lights and trying to match the par?

I have a similar set up as you, 18" depth with 150 watt mh and 2 OR3 bars.

I think the corals will grow anywhere you put them in the tank. I used to think about placement but I've learned that acros/sps will grow anywhere in my tank, any height even the ones I drop behind the rocks start growing, IMO its not comparable to led lights. All my other tanks are led lights and coral growth never compares to my mh tank. Just my 2 cents good luck

I’ve been running halides on this tank since it started up 6-7months ago.

 

[reef’r]

slimer

5/31/23

I dont have a side view of it because #slimer but it's about 15" tall now, maybe a bit taller.
4/23/26

That's 'fast' but honestly, its still kinda slow.

200 par at the bottom, now getting 350+ at its top

I’ve had some frags from my last tank, they were under T5/LED that have not done much in a year

Bc fire cracker may 2025

No name, may 2025

no name, may 2026

BC firecracker, may 2026

 

[BeanAnimal]

200 par minimum. I have acros in my 150 that get 200 par on the bottom and doing well.

You can't compare readings from LEDs and MH. They aren't even close in spectral distribution.

 

[rtparty]

I have a mixture of halide grown and led/T5 combo grown. I’ve been adding to my tank under halides for the last 6 months

My experience has been LED grown SPS take months to acclimate to halides. When they do, they look amazing and seem to be bulletproof but it is a very slow process as the corals change their biology to handle the different light

 

[BeanAnimal]

to the OP:

You don't need 400W fixtures above a 16" deep tank with coral sitting near the top. If you want to run them, you may be able to get the coral to acclimate, but most of us ran DE 150s or SE 175s over tanks that size, some people ran 250s with care. When optimized reflectors came out, the 250s were too much, let alone 400s.

 

[X-37B]

My experience has been LED grown SPS take months to acclimate to halides. When they do, they look amazing and seem to be bulletproof but it is a very slow process as the corals change their biology to handle the different light

I have seen the opposite when I moved around 19 frags to my halide system. Several have visible growth and they have only been in the new tank for a month.
One new frag which is some type of yellow polyp stag was removed and put in the halide system. It has grown and started to encrust. The one in my 150 has not encrusted or grown.
The difference is par value is 250 under leds and 500 under halide.
Anyway just my observation so far and the reason I setup the growout syatem was to compare the 2.

 

[rtparty]

I have seen the opposite when I moved around 19 frags to my halide system. Several have visible growth and they have only been in the new tank for a month.
One new frag which is some type of yellow polyp stag was removed and put in the halide system. It has grown and started to encrust. The one in my 150 has not encrusted or grown.
The difference is par value is 250 under leds and 500 under halide.
Anyway just my observation so far and the reason I setup the growout syatem was to compare the 2.

A few of mine showed no signs of the swtich. Millis, ORA Joe the Coral, and a couple others didn't seem to mind but others are almost a year in and still trying to adjust

 

[X-37B]

A few of mine showed no signs of the swtich. Millis, ORA Joe the Coral, and a couple others didn't seem to mind but others are almost a year in and still trying to adjust

Interesting as I took several that have been in my systems for over a year with little to no growth.
They have already responded to the halides.
When I ran my 120 before running halides every coral that went into that system was from leds. All grew quite well and I dont remember any having growth issues except for maybe to much growth, lol.

 

[Biff0rz]

I’ve had some frags from my last tank, they were under T5/LED that have not done much in a year

Bc fire cracker may 2025

No name, may 2025

no name, may 2026

BC firecracker, may 2026

I've had a coral take 2yrs to take off. It's annoying and unexplainable. I've had several like this that are just stubborn. I've moved them, let them be, changed lights, etc. They just grow when they decide to. Again, you have plenty of par. If you give them good flow and more importantly, stability, they will grow.

 

[X-37B]

I've had a coral take 2yrs to take off. It's annoying and unexplainable. I've had several like this that are just stubborn. I've moved them, let them be, changed lights, etc. They just grow when they decide to. Again, you have plenty of par. If you give them good flow and more importantly, stability, they will grow.

I have a few like that, just slow growers.
Some dont even look like the frag they were when put into the system.
Example : my Colliderscope growout frag does not even look like the same coral. Everyone elses looks normal.
8 months growth.

 

[X-37B]

Here is what the Coliderscope colony should look like.

 

[reef’r]

I have a few like that, just slow growers.
Some dont even look like the frag they were when put into the system.
Example : my Colliderscope growout frag does not even look like the same coral. Everyone elses looks normal.
8 months growth.

I’ve somewhat noticed this too. I wonder if acropora is more inclined to grow in a more “table” structure when under halide….. that would work for me lol I much prefer them tables out than long branches

 

[reef’r]

to the OP:

You don't need 400W fixtures above a 16" deep tank with coral sitting near the top. If you want to run them, you may be able to get the coral to acclimate, but most of us ran DE 150s or SE 175s over tanks that size, some people ran 250s with care. When optimized reflectors came out, the 250s were too much, let alone 400s.

I actually did have a piece that I’ve seen grown under crazy par number with LED bleach out when I had it right under one of the bulbs. It came from Adam and I asked for all the pieces to be from his halide tanks…. I thought that was weird

 

[X-37B]

I’ve somewhat noticed this too. I wonder if acropora is more inclined to grow in a more “table” structure when under halide….. that would work for me lol I much prefer them tables out than long branches

Dont thinks so as many others running leds look "normal".
For my system I think its flow related. It sits at the front middle of the system. It gets swept twice from both 6255's and its rather strong because it bounces off the front glass. Even BC Adam said it was a quite unusual growth pattern.

 

[Reginald Reefer III]

Must... resist... urge... to post... thiccc meme....