Lighting for 20" acroporas-only cube

[meermann]

Hi guys,

I got stuck at this step: I ordered 20" cube (20x20x18, 29 gallons) and now I have struggles to choose between one AI Prime 16HD, two of AI Prime 16HD and one AI Hydra 32HD.

I plan to grow acroporas only. But I guess there will be plenty empty space along the glass walls because I need to clean them somehow. I mean the SPS will not be distributed in the entire tank, rather in the middle.

Is one AI Prime 16HD enough for my depth of 18"? If no, what's the best option to keep acroporas healthy and fast-growing? Does a pair of AI Prime 16HD provide significantly wider spread than one Hydra 32HD on such small length of 20"? Ah forgot to mention, there is also an overflow box in the tank - right in the center of rear wall. Its size is approx. 11", so 2 Prime anyway will be installed pretty close to each other.

Thank you!

 

[vetteguy53081]

Ai prime would be ideal

 

[Bpb]

Two AI primes. Always better to have light coming from multiple angles/sources than just one. Not so much an issue of raw horsepower, but Moreso mechanism of delivery. A panel of lower powered diodes covering the tank footprint is better than a single multi chip of equal total power in the center

 

[Shaka_Reefer]

Neither, get a radion xr15 g5 pro or the kessil a360x

 

[nereefpat]

It looks like the distance between pucks on a Hydra is 4.5" center to center. You could space 2 primes *slightly* better at 6" on a 20" tank...not sure if it's worth it or not.

 

[Viking_Reefing]

Why not a philips coral care gen2? It should blow most other fixtures out of the water in terms of light dispersion, something you are going to need when you colonies starts taking of.

 

[meermann]

Why not a philips coral care gen2? It should blow most other fixtures out of the water in terms of light dispersion, something you are going to need when you colonies starts taking of.

There is ATI Straton with almost the same light dispersion abilities and also good-looking, but I consider to use time-proven solution. Philips Coral Care Gen2 is great device, but pretty new.

 

[meermann]

It looks like the distance between pucks on a Hydra is 4.5" center to center. You could space 2 primes *slightly* better at 6" on a 20" tank...not sure if it's worth it or not.

Yeah, I calculated that maximal distance between the pucks of 2 Primes will be around 8-9 inches in my case. Hard to estimate will it help or not...

 

[Bpb]

There is ATI Straton with almost the same light dispersion abilities and also good-looking, but I consider to use time-proven solution. Philips Coral Care Gen2 is great device, but pretty new.

Sort of. Really the only truly new aspect of it is the software. The fixture itself is one of their high bay lighting type fixtures, just with different colored diodes. Otherwise it’s the same unit. Same guts, same housing, same PCB. I’d wager there may be more of those in operation around the world than nearly all other reef specific led units from all other companies combined

 

[infinite0180]

I had an xr15 pro over a 18x18x18 and it was good but there was some shadowing. Out of what you listed as options id go with two primes. That should cover the tank from all angles...

 

[frank1203]

I’d get the hydra 32s. You can Just turn down the intensity and till you get the PAR you need. And Incase you upgrade in the future you can add 1 or 2 depending on how big of thank you’re getting.and not worrying about selling the prime.

 

[Steven Garland]

2 16's over a 26. You can achieve better coverage and alleviate the par hot spots with the 26.

Just crank them badboy's up lol. Are you going for a specific par ? Depending on which acro's you are wanting,"lower-medium" par acro's or par hungry tenuis or higher end acro's ?

 

[Abhishek]

This was old tank of mine . I removed all the montis later and had only and only acroporas . The tank was lit by 400 watt Geissrmann mega chrome and then Ushio 14 K , 4 ATI T5s ( blue plus ) and 2 Reefbrite XHOs .

It was a 30 inch x 30 inch x 18 inch tank . If your aim is only acropora and mind you only acropora , you would long for much
More than 1 AI Prime . Of course your mileage might vary and you might keep lower light tenuis or smooth skin acros but if you are into high light loving ones , you should look into multiples like 2-3 or mounted high like above 12-16 inches for better coverage and high PAR .

 

[Bpb]

This was old tank of mine . I removed all the montis later and had only and only acroporas . The tank was lit by 400 watt Geissrmann mega chrome and then Ushio 14 K , 4 ATI T5s ( blue plus ) and 2 Reefbrite XHOs .

It was a 30 inch x 30 inch x 18 inch tank . If your aim is only acropora and mind you only acropora , you would long for much
More than 1 AI Prime . Of course your mileage might vary and you might keep lower light tenuis or smooth skin acros but if you are into high light loving ones , you should look into multiples like 2-3 or mounted high like above 12-16 inches for better coverage and high PAR .

I know it was probably a lot more blue in person, but I can’t stress enough how much I prefer that natural shallow water mid day look over the heavy blue.

 

[Abhishek]

I know it was probably a lot more blue in person, but I can’t stress enough how much I prefer that natural shallow water mid day look over the heavy blue.

Actually it wasn't much bluer than this especially with Ushio 14K 400 watt . Like you, I also cant stand any blues in my tank.May be thats why I never moved to leds and run lesser blue plus than KZ New Gen on my new tank

 

[meermann]

2 16's over a 26. You can achieve better coverage and alleviate the par hot spots with the 26.

Just crank them badboy's up lol. Are you going for a specific par ? Depending on which acro's you are wanting,"lower-medium" par acro's or par hungry tenuis or higher end acro's ?

I expected to get PAR around 250-350, would be enough I guess. I've seen few videos with Reefer 170 (24" length) and only one Hydra 32 and the growth of acros was perfect IMO. That guy mentioned he had even around 450 PAR about 8-10 inches below the water level.

 

[meermann]

This was old tank of mine . I removed all the montis later and had only and only acroporas . The tank was lit by 400 watt Geissrmann mega chrome and then Ushio 14 K , 4 ATI T5s ( blue plus ) and 2 Reefbrite XHOs .

Nice tank. How much PAR was reached under the metal halide? 400W looks a bit oversized for 18" depth IMO.

 

[driftin]

I may be way overkill, but I have three AI's over my -almost- cube tank (31" x 26"). Two 52's and one 64. It was a big investment (done over time) but I felt my rockwork layout kind of necessitated it. Two running lengthwise and the third along the end opposite the overflow. That spread of light really cuts down on shading, gives me lots of flexibility on intensity.

If I was covering a 20"x20" I would still go with two of the HD52's or 64's.

 

[meermann]

I may be way overkill, but I have three AI's over my -almost- cube tank (31" x 26"). Two 52's and one 64. It was a big investment (done over time) but I felt my rockwork layout kind of necessitated it. Two running lengthwise and the third along the end opposite the overflow. That spread of light really cuts down on shading, gives me lots of flexibility on intensity.

If I was covering a 20"x20" I would still go with two of the HD52's or 64's.

In Germany where I live 64 costs around 2 times (well, 1.7) more expensive than 32, so I would prefer to have two 32's than one 64, also they are allow to have more flexible setup and total power is almost 180W)

 

[meermann]

Thank you guys for your replies.
An update:

1. Because of my cube still wasn't made by its manufacturer, I ordered another one with slightly different dimensions. Now it's 26x20x20 - just a bit longer than well-known Reefer 170. It's in the warehouse and will be delivered next week exactly as I was promised.

2. I already bought one Hydra 32HD, despite of tank size will be changed a bit, I guess it still will be enough to light the central rock in the beginning (I understood there will be dark area in the left and in the right, but I wouldn't like to utilize it anyway, rather prefer airy design).

3. Now I consider to buy either another Hydra 32HD or something like Giesemann Stellar/Aquatic Life T5 HO to provide better spread. The price is almost the same in both cases, what could you recommend me to use?
I've seen the video from BRS that has shown Aquatic Life and something like Kessil a360 over Reefer 170 - almost my case, but also I've seen the videos with only Hydras over the bigger SPS tank.

4. Primary goal remains the same: acros-only tank.