14k to 20k will this be ok for crocea?

[SaltyMember]

Hi, I have a 65gal 24inch tall tank w/ 2 x 250wt SE EVC 14k bulbs. I am getting close to replacing my bulbs and I am considering switching to EVC 20k bulbs primarily for color.

What I am concerned about is my crocea clam that currently sits midway in the tank directly under a bulb. I know the 20k bulbs I am looking at have less par than the bulbs I use now (59 PAR vs. 71 PAR according to Sanjay's site). Will this decrease in PAR negatively affect my clam? I would like to keep my clam at it's current placement if possible but I could move it higher up if needed.

I would appreciate opinions. Thanks!

 

[Ti]

Nope, ran clams under both.

 

[SaltyMember]

Thanks Ti,
I just wanted to hear from somebody with more experience with clams.

I appreciate the help.

 

[Ti]

np
my maximas r still going strong and sucking up Ca

 

[critterkeeper]

20k bulbs are dimmer - and they last about half as long as 10Ks.

If you want more blue, add blue fluorescents and have more light, rather than less.

 

[SaltyMember]

I never heard of 20k bulbs having a shorter lifespan that 10k bulbs. Do you have any references for me.
thanks

 

[jay24k]

It's true. They do generally need to be replaced more. The higher the spectrum, the quicker it seems to lose intensity. I don't have any references off the top though. I wouldn't say half as long but I would say maybe 2/3rds.

 

[SaltyMember]

thanks,
I might have to rethink this then..

 

[jay24k]

Ever notice the radiums how often they need to be replaced? or the XM 20k's? Adds up after awhile. Also depends on what growth you want too.

 

[critterkeeper]

Depends on the ballast and bulb, but there's a general rule of thumb that the higher the kelvin number the shorter the bulb life.

6,500K generally go 12 to 18 months, 10K anywhere from 12 down to 6 depending who you ask, 20K 6 months at best...

FYI - I've tried them all - and will never buy a 20K again.

 

[SaltyMember]

thanks for the input everyone,
I've decided to stick with the 14k EVC bulb. It is a pretty blue bulb and has decent par. I don't think I want to give up the growth.