8 bulb or 6 bulb fixture for 100 gallon tank??

[FWTXReefnerd]

Hello,

 

I'm about to set up a 100 gallon SPS tank. After much thought & research I’ve decided to go with an ATI “Sunpower” t5 fixture. My tank is a 4 ft tank so I’m going with the 48” fixture. However, I’m torn between getting the 8 bulb & 6 bulb fixture. I think the 8 bulb would give me better lighting, but I’ve also heard the2 extra bulbs would just spill out of the tank. 
 

Does anyone have any experience with this fixture on a 4 ft tank? Am I good to get the 8 bulb? Or should I get the 6? My objective is to get the most PAR possible & have an even blanket of light. Please let me know your thoughts.

 

 Thanks!

 

-Nathan B.

[NoOneLikesADryTang]

How wide is the tank? 
 

We have an 6 bulb, over and Innovative Marine SR80, which is about 20” of display width. The 6 bulb covers it perfectly, without much light spill. 

[FWTXReefnerd]

5 hours ago, NoOneLikesADryTang said:

How wide is the tank? 
 

We have an 6 bulb, over and Innovative Marine SR80, which is about 20” of display width. The 6 bulb covers it perfectly, without much light spill. 

Did you get a par meter reading on the tank??

[NoOneLikesADryTang]

55 minutes ago, FWTXReefnerd said:

Did you get a par meter reading on the tank??

I did, but I don’t remember them. If you’d like, I can try to take them again this week. Are you just looking for max par? 

[mcarroll]

On 8/22/2021 at 3:03 PM, FWTXReefnerd said:

Hello,

 

I'm about to set up a 100 gallon SPS tank. After much thought & research I’ve decided to go with an ATI “Sunpower” t5 fixture. My tank is a 4 ft tank so I’m going with the 48” fixture. However, I’m torn between getting the 8 bulb & 6 bulb fixture. I think the 8 bulb would give me better lighting, but I’ve also heard the2 extra bulbs would just spill out of the tank. 
 

Does anyone have any experience with this fixture on a 4 ft tank? Am I good to get the 8 bulb? Or should I get the 6? My objective is to get the most PAR possible & have an even blanket of light. Please let me know your thoughts.

 

 Thanks!

 

-Nathan B.

A 4-tube fixture can actually light a very deep tank, depending on the tank and what you want to keep.  Nothing has changed with florescent fixtures in the last 20 years that would make a new florescent fixture perform any worse than that.

 

Moving up to 6- or 8-bulbs should be pretty optional.....but I'm not sure what your goals are.  

 

You can vary the height of the fixture to prevent light-spill, BTW.   That said, if you have an requirements for how high the fixture needs to be (eg for aesthetics or whatever) then you might be more limited in what you can do to prevent spillage.  In that case, sticking with the minimum/correct number of bulbs would obviously be a requirement.

 

Also, 100 gallons by four feet sounds like a "deep 90 gallon" to me, but what are the tank's actual dimensions?  What are you planning to do with the tank?