# Need to replace bulb in my PC/CFL



## Mad Professor (Oct 3, 2008)

My new fixture "coralife 30" 65watt" came with a 50/50 bulb *10k/Act 03* and well, I haven't been satisfied with the bulb. I keep getting brown algae or known as diatoms all over the 44 gallon, and I think it's the actinic side of the 50/50 bulb is to blame. I'm controlling it with two 4 hour time blocks, 8-11AM and 8-11PM but the wisteria and java ferns are surviving but not growing or thriving. The same plants in my 20 gallon with NO florescent 20 watts are growing, and thriving and have doubled in size this last month.

I want to change bulbs from 50/50 to a 6700k bulb, but I can't find it. Anybody know of a good site to buy this bulb from or if a 8000k 55W or the GE 9325K 55W from www.drsfostersmith.com would do fine?

Btw 10k is pretty white, I think I need to turn down the kelvin by a few degree's.

~Mp


----------



## jones57742 (Sep 8, 2007)

Mad Professor said:


> I want to change bulbs from 50/50 to a 6700k bulb, but I can't find it.


MP: do not know if you have seen a 6700K bulb in person but the light which is emitted has an ugly, at least to me, yellowish tint.

You might consider this *square pin bulb* if you have a square pin connector (please note that a 6700K bulb is available also).

If you have a straight pin fixture this a *6700K bulb.*

TR


----------



## Guest (Apr 24, 2009)

the CFL 6500k is a nice bright white. thats what i use in my 25GL.


----------



## Mad Professor (Oct 3, 2008)

I don't know if I want a dual daylight bulb for the PC/CFL fixture

I just check the one in 20 watt it's flora-glo 2,800K with a 90 Deg. Lux whatever that means, But It looks fine to me, like a dim shoplight. I don't know if Lux is the same as CRI or not. I have another flora-glo 2800K 65 Lux for the 15w fixture for the 10Gal in my bedroom and its kind of a whitish purple, but then again I haven't burned it in yet, and it's combined with a sun-glo which is 4,200 K.


10k is pretty white to me, it could be the river stone gravel I have in the tank though.

Could my 65 watt ballast handle a 55 watt bulb?
65w / 44g = 1.4wpg
55w / 44g = 1.2wpg

Also the tank is 2 feet deep, so would the intensity of the light matter?


The local pet store here *Petsmart/petco* have a coralife 10k bulb.

What should I get actually?
Coralife 6,700 K bulb 65w
All-Glass 8000 K bulb 55w
GE 9325 K bulb 55w
Coralife 10k bulb 65w
or 
Coralife Dual Daylight 6700/10k bulb 65w

All straight Pin arrangement.

Maybe I should try a 10k bulb? 

I wish there was a way to kill the actinic side of the bulb.


----------



## jones57742 (Sep 8, 2007)

Mad Professor said:


> I don't know if Lux is the same as CRI or not.


I do not believe that they are equivalent units of the measurement of energy.

Lux is relevant to brightness perceived by a human.

CRI I believe (very foggy from reading a Barr report many years ago) is relevant to the to energy (including non-visible energy) available to plants.




Mad Professor said:


> Also the tank is 2 feet deep, so would the intensity of the light matter?


MP: not if the tank is properly maintained.




Mad Professor said:


> What should I get actually?


MP: the Coralife Dual Daylight 6700/10k bulb 65w IMHO
and I am presuming that you have checked your fixture to insure that it is straight pin receptive.

TR


----------



## Mad Professor (Oct 3, 2008)

Yeah its a straight pin.

I can get the "Current 22" SunPaq Dual Daylight
6700ºK/10000ºK 65W, CD-21119
$23.99" from drsfostersmith.com

https://www.drsfostersmith.com/product/prod_display.cfm?pcatid=13314&prodid=25141&catid=3

If there is no protest from anybody I'll probably get it tomorrow night.

Thank you everybody.


----------



## jones57742 (Sep 8, 2007)

Mad Professor said:


> I can get the "Current 22" SunPaq Dual Daylight
> If there is no protest from anybody I'll probably get it tomorrow night.


MP: sounds good: I have had good luck with Current USA bulbs but for some reason Marine Depot no longer carries them.

BTW: is your memory of CRI the same as mine?? I cannot now find the Barr Report treatise.

TR


----------



## BV77 (Jan 22, 2005)

another good place to find bulbs http://www.ahsupply.com/index.html


----------

