RB's for 300 gallon

[BradVincent]

I need to replace some Royal Blues.  I am using LXK0-PR04-0016's, but everything says they are discontinued.  I can still buy them, but there are probably better options.  What should I use?

[evilc66]

There's nothing else that I know of that would replace a K16 royal with another quality LED array. Your only other choice is the cheap Chinese arrays.

 

Luminous Devices does have high power royal blues, but they are high current and low voltage, so you would have to change your driver setup.

[BradVincent]

So I can still order k16s from mouser around $17 each or Ms from ledgroupbuy for $10.75.  Which is a better deal?  What current should I use?

 

 I'm thinking 1000ma for 4 Ms in series since I am using LDDs.  I've run the K16s either singly or 2 in parallel anywhere from 350ma to 1000ma, been disappointed with their lifespan so maybe I should stay on the lower end, but most of my problems went away when I added a canopy fan.

[evilc66]

K16's are a lot of power in a small area, so getting the heat out is critical. Your heatsink may not of been able to get the heat away quick enough creating a local hot spot. Increasing the airflow around the mounting area of the K16 on the heatsink will remedy that, as it seems you have found out. Provided that temperatures are in check, they should last as long as any other LED. As for current, go for as high as your heatsink will allow.

 

While the Lux M royals are good, nothing beats the K16 for energy density in a high quality LED (save for the Luminous LEDs, but they are high current, low voltage like I mentioned before)

[BradVincent]

I am looking at cost per watt.  8xMs are $86 for 44 watts on 1 strand, or $1.95 per watt.  1 K16 is about 42 volts on 1 strand.  At 350ma, thats 14.7 watts at $1.15 per watt, but I need 3 times as many strands.  But I need a lot more soldering to do 8 Ms, and if one fails, they all fail.

 

I wonder if DIY is really even worth it anymore.   Costs are higher than 2 years ago, while premade fixtures keep getting cheaper. 

[evilc66]

Yeah, it's not as cut and dry as it used to be for justifying going DIY on cost alone. Although, you still can't get many fixtures with the right mix of LED colors. The lack of warmer whites on higher end fixtures is baffling to me, and only Nanobox uses limes/mints which to me is far superior to using green LEDs.

[BradVincent]

What is the most cost effective commercial fixture other than no name Chinese?  Even if I don't switch my main tank, I am in the market for a frag tank.

[evilc66]

The AI Prime is pretty affordable for what it can do, but you are limited on coverage area and overall intensity. Larger fixtures command larger price tags. The Chinese black box fixtures are where it's at for best value, but smallest feature set.

[BradVincent]

Is fleabay the best way to get cheap Chinese fixtures?

[evilc66]

I tend to suggest you avoid eBay for this. Stick with brands that have a reputation of good quality, good LED mix, and good customer support. It's the LED selection more than anything. A lot of the Chinese resellers on eBay just don't have the right LED mix (still using high kelvin whites, etc...). Amazon sells MarsAqua and Galaxy Hydro fixtures, and those are pretty well reviewed.