PAR for a SPS tank

[BrentH]

I have be thinking about using the radium 20k with my new tank with the lumatek ballast from what I've read it seems the 400 watt would be the best choice for par etc.... With sps ? I have always liked the 20k look but have always used 14k for the better par. Do u think that 20k radiums would be ok 2 of them on a 5 foot tank

 

[110galreef]

You can cover a 5' tank fine with 2 400w MH's,just depends on the reflectors and how much room above you have. You will get more PAR from the Radiums than my XM 20k's for sure.

...Im covering a 5.5' tank with 2 400w XM20k mh's. But i have 4 T-5 for some help. Plus my tank is 36" front to back.

 

[BrentH]

Ok I using the hamilton spider reflectors there's ok and I have a canopy so the fixtures are about 10" cool ill do it ..... And my other tank is the one with the lumatek ballast also that I am doing the 250 hamilton bulb I'm going to take it slow like u said and slowly acclimate to the 250 hqi setting then maybe down the road go with the radium 400 watt but I don't want to fry stuff most of my frags came from
U and are doing good actually since I switched ballast there is more poloyp ext and the corals lower down seem to be happier .... Dn so
Much to know in the sps game ....but its fun

 

[WindyCityFlyer]

Might be a easy question but how do you test your Par readings on your tank? t

 

[jerpa]

With a PAR meter. Here is the most popular model in our hobby.

Apogee PAR Meter

You can also save some $$$ and just buy the sensor and hook it up to a multimeter. This does require you to be able to multiply by 5 though.

 

[110galreef]

I bought the apogee sensor and a decent multi meter. About $175 for the set. Take millivolt and multiply by 5. Works great and more than half the cost of the typical apogee par meter

 

[Newbie Aquarist]

I bought the apogee sensor and a decent multi meter. About $175 for the set. Take millivolt and multiply by 5. Works great and more than half the cost of the typical apogee par meter

Which sensor did you get?
This one:
SQ-110: Sun Calibration Quantum Sensor.

Or this one:
SQ-120: Electric Calibration Quantum Sensor

 

[110galreef]

Sq-120.....that one is calibrated for the electrical light sources we use. They also have a guide inside which shows the output variation of different light sources and the sun when using it

 

[Newbie Aquarist]

Sq-120.....that one is calibrated for the electrical light sources we use. They also have a guide inside which shows the output variation of different light sources and the sun when using it

So I can get this right, what ever the reading is you multiply it by 5. And the setting is placed on millivolts correct?

 

[110galreef]

I bought the sensor sq-120, a reliable multi meter for like $40, and I also bought a set of aligator clips to attach the loose wire ends of the sensor to the multi meter from lowes. Since the standard pointed ends that come with the meter I didn't fell like cutting so I could use noramlly around the house.

I also fabbed up a nice arm for putting the sensor at various spots w/o getting my arm wet!

Here are some pics.

 

[Newbie Aquarist]

Thanks for clearing that up. Picture make it more clearer.

 

[rlpardue]

Just read through this thread; quite informative. It seems people are solving situations which are similar to mine, but a little different. Apparently I have an unusual ballast - a 400w Coralvue dimmable. I'm hoping to get a nice crisp blue-white color out of the lights - my tank's water level is only 22" deep, so I figure that running 400w 20k/bluer lighting will give me the same PAR as a 250w 10k bulb.

Would anyone recommend that I do NOT run Radium 20k bulbs with this ballast? It seems like many people who have my ballast run Reeflux 12k bulbs and sound satisfied.

NOTE - I'm using some Lumen Brights too, and my tank is 5x2x2.

 

[sirreal63]

Are you running three bulbs or just two?

 

[MikeTR]

new bulbs are in, 150w phoenix overdriven to 175w. I feel this is exactly where things should be. Not totally sold on the phoenix but will do for now. I'll try an iwasaki in about 8 months when these are toast.

 

[110galreef]

I plan to test either ushio 14k 400w SE or Radium 20k or Nueco 14.5k(aquastar) bulbs next go.

I like the XM 20k, but had to even it out with a 10k T-5, ATI purple+ & coral+, & hamilton blue). So I think a whiter bulb and Higher par will help and allow me to run a blue+ instead of the 10k and still net me a nice white/blue color with even more par!

14K MH & 2 ATI blue+ &
2 coral+ or actinic??

I will see what I need when I cross that road!

Ok, picked up 2 slightly used Reefux 12K, as well as 2 new Ushio 14k! PAR number soon!

Here I updated to show the MH only PAR numbers. (orange)

After about 4.5mos of bulb use my PAR seems down maybe avg 15%. Hard to say exactly as I redid some rock and corals and things have moved. The numbers just above the water surface and below tho fell ~ 10%, with the greatest drop in PAR near the bottom.

MOS...any radium numbers compared to your other bulbs?

 

[MikeTR]

new bulbs are in, 150w phoenix overdriven to 175w. I feel this is exactly where things should be. Not totally sold on the phoenix but will do for now. I'll try an iwasaki in about 8 months when these are toast.

And here we are just 2 months later. I think we're on the right track.