3 questions about VHO vs T5s

[chopsuey]

I plan on swaping my 4 96w PCs with either 4 VHOs or 4-8 T5s depending on space. But I still have a few unanswered questions. See pic below for my current setup.

Question 1:
Bulb for bulb which run cooler T5s or VHOs?

Question 2:
Bulb for bulb which use the least amount of electricity?

Question 3:
Bulb for bulb which will give a deeper blue/purple atinic color to supplement 10k MH?

http://isoclan.com/saltwater/11.09.06/slides/DSC02055.JPG

Given my current setup what is your opinion on the best fit for me?

[oct2274]

I'm not sure that either the T5's or VHO's run any cooler than the other, but the T5's are much brighter per watt than VHO. both have good blue bulbs now. Just make sure if you get T5's you get the T5HO, not regular T5, and that you get individual reflectors for each bulb.

[aninjaatemyshoe]

"Question 1:
Bulb for bulb which run cooler T5s or VHOs?"

Really, does it matter? The real issue is their efficiencies. T5s are way more efficient than VHOs, both bulb for bulb and especially when you factor in individual reflectors for the T5s. Now, let's say you were to choose between 4 VHO bulbs or 4 T5 bulbs. Not only will the 4 T5s add less heat (less wattage bulb for bulb), but they will add a good deal more light.

"Question 2:
Bulb for bulb which use the least amount of electricity?"

Again, the question is about efficiency. T5s use less energy than a VHO bulb of similar length. This is unless you are using an Icecap ballast, in which case they will be ran at similar wattages. However you will be getting tons more light out of a T5 on Icecap than you would out of VHO.

"Question 3:
Bulb for bulb which will give a deeper blue/purple atinic color to supplement 10k MH?"

Perhaps the last saving grace of VHOs is that many people seem to prefer its actinics over what is available in T5s. Even UVL (formerly URI) has commented on the fact that they have yet to match the quality of their VHO super actinics in their T5 super actinics. I've only used T5 actinics and not VHOs so I can't really comment on this aspect except to say that I find T5 actinics quite adequate.

[arc eye]

"Now, let's say you were to choose between 4 VHO bulbs or 4 T5 bulbs. Not only will the 4 T5s add less heat (less wattage bulb for bulb), but they will add a good deal more light."

So are you saying that 440watts of VHO put out less PAR than only 216watts of T5HO?(assuming these are 4ft bulbs). Could this really be? Even with the individual reflectors factored in for the T5s, greater than twice the output at half the wattage is sort of suspect.

................not that I have any real experience or a par meter for comparison (although I may very shortly), but from all the chaotic info. I have sorted through over the past few months it seems that the difference between VHO, PC, and T5 watt for watt isn't as great as people think. nor some of the individual reflector claims.........just my 2 cents

that said I just so happen to have on the way a 2 lamp VHO retrofit and a 2 lamp T5HO retrofit with icecap reflectors. I will share my thoughts after running both, however, a stright line comparison is unlikely since I am not planning on getting the same bulbs across the board.

...curious to see what other think.

[MSU Fan]

It's not a matter of wattage necessarily - it's a matter of efficiency or effectiveness.

But let's re-phrase the question:

If the effective output of T5s and VHOs are close enough to be called the same/similar, and that heat is comparable, but one needs 110w per bulb and uses more space, and the other only needs 54w/bulb and less space - which sounds better to you?

[arc eye]

I guess what I am saying is that I am skeptical that a 54w T5 even with an individual reflector is more efficient than a 110w VHO. I just can't seem to find data to support it. emphasis on data

[DarG]

Actually, the T5 uses more space, sort of. The T5 with a reflector is going to take up 2 - 3", depending on refector. A VHO T12 is 1 1/2", the reflector is internal on the most commonly used VHO's. Most dont use external reflectors. But in reality, they take the same space because the end cap mounts are the same width at about 2.5". If you float the endcaps the VHO actually will use less space. If you dont use a reflector with the T5, you may as well use VHO, you'd be better off.

Arc Eye ... there are lumen / watt and other quantitative comparisons of VHO and T5. Nobody seems to be able to provide specific data of reflector effectiveness however. All I can go by is my personal experience with both T5 and VHO and T5 with individual reflectors and with one large reflector. Thats personal experience with observation too, not even instruments.
I built my light rack to accomodate either VHO or T5. The only reason why I would use the VHO option was for the UVL super actinic lamps. I never was impressed much by the T5 super actinic. UVL's T5 super actinic is a signifigant step up in output compared to a cheap super actinic T5 like Current USA's chinese made lamps for example. But still not really impressed by it. I have to say though, on the IceCap ballast which I just switched to, the UVL actinic T5 is not too shabby. First time I have seen a super actinic T5 atleast approaching that of VHO. The color is good and the output is respectable. With the reflector and the IceCap ballast, honestly speaking, I dont think that VHO super actinic is going to put more light into the tank than the overdriven UVL T5 super actinic. Color may be a bit better with the VHO actinic but I dont think it will compete in output, again, into the tank. I thought it may be close with the T5 at 54 watts. I thought that with the color edge, it may be worthwhile to use VHO over T5 Super actinic at 54 watts. I may be wrong, the T5 may have signifigantly more output making it into the tank at 54 watts with the reflector. But with a visual comparison, I thought it may be worth trying the VHO actinic over the T5. But at 85 or 80 watts, I dont think the VHO can compete in regard to light in the tank. I think the color is close enough to make it not worth losing the output advantage that I am condident that the overdriven T5 super actinic will have.

For what it's worth and I'm not invested either way.

[aninjaatemyshoe]

"I guess what I am saying is that I am skeptical that a 54w T5 even with an individual reflector is more efficient than a 110w VHO. I just can't seem to find data to support it. emphasis on data"

I think what you mean to say is that you are skeptical that a single 54W T5 puts out as MUCH LIGHT (not more efficiency) as an 110W VHO, both being of the same length. To answer this issue, first it has pretty much been established that the individual reflectors on a T5 bulb doubles the output into the tank over having one single large reflector for all bulbs. VHO bulbs do not use individual reflectors as they are just too thick for it to improve things much. Often one doesn't even use any reflector at all and perhaps just has the canopy painted white to reflect light down into the tank. So lets just say that, individual reflector alone a T5 is pretty evenly matched with a VHO. Now, in pure efficiency, T5s also hold an advantage. They output about 90-100 lumens per watt, whereas VHO outputs about 70-80 lumens per watt. Last but not least, T5s do not loose their output nearly as fast as VHOs. A typical T5 bulb can be ran about 1.5 years before the output has reduced to the point where it needs changing, and a typical VHO bulb can be ran about a year. This means that a 6 month old T5 bulb has lost a lot less of its output than a 6 month old VHO bulb. All things considered, it is pretty obvious that T5s blow away VHO in terms of output and efficiency.

[DarG]

Most VHOs for aquarium use have the internal 180 degree reflector. Or I should say that most people buy the VHO's with the 180 degree internal reflector. No comparison in effectiveness between the internal reflector and a T5 reflector. But the VHO internal reflector is much better than no refector at all.

[Shade00]

UVL's VHOs all have 180 degree internal reflectors. Well, not the value Aqua-D line, but the normal bulbs do.

Now, while the internal reflector may put some more light into the tank, keep in mind that the VHO bulb is going to put out far few lumens per watt than a T5 - so, if a VHO puts all of its lumens into the tank, then it'll probably be ABOUT the same amount of light as a 54w T5HO.

[arc eye]

I'm thinking maybe I'll buy one actinic and one daylight in both VHO and T5 and do a comparison (I'll have to look into acquiring/borrowing a par meter).

If the T5s color and output seem pretty comparable I may switch out the VHOs for a few more T5s (the VHOs are coming with an icecap 430 ballast).

Anyway, I was never questioning the efficiency of the T5s in an absolute sense merely in a relative sense. i.e. how many well reflected T5 watts equal one decently well reflected VHO watt in terms of light output.

For energy consumption's sake I'm really hoping T5s come out on top on all accounts

sorry for sort of derailing the thread

[aninjaatemyshoe]

If you are comparing both the VHO and T5 on an Icecap ballast, there is no question that you'll get more out of the T5. Icecap increases the output from T5s by about 40%. If you can get a PAR meter and set up the test, then it would nice to know what the difference is. I would say a fair comparison would be between the VHO with internal reflector vs. the T5 with individual reflector as this is the normal mode people run each.

[arc eye]

my thoughts exactly.........in all honesty I probably would bought all T5s, but I was looking used and found both retrofits for fairly cheap.

[arc eye]

Also, can the 430 ballast power more than 3 bulbs? all the sites selling them claim they can power up to 324watts over a maximum length of 12ft. Four or five T5s would meet the power restriction, but not the length restriction.......any thoughts?

[arc eye]

chopsuey, how high above your tank are your PCs?

[DarG]

Arc Eye, I believe that you are limited by both wattage and number of bulbs (total bulb length) with the 430 and 660.

Another thought ... you can run both T5 and VHO at the same time on a single IceCap ballast. So you can run super actinic VHO and the other spectrums with T5. That was something else I also considered. But with the T5 super actinic looking pretty good on the 660 I decided to stay with it for the addional par vs. the VHO.

[aninjaatemyshoe]

Actually, it is my understanding that the 430 ballast can only run 2 bulbs, T5 or VHO. You need the 660 ballast to run 4 bulbs.

One more thing to consider is that you'll need to have really good circulation for T5s on Icecaps. This means good quality fans running along the length of all bulbs. It's particularly important to cool the ends of the bulbs. If the bulbs over-heat their output drops dramatically. I cannot emphasize this enough. IMO this is the number one drawback to using the Icecap ballast for T5s.

[DarG]

True on the cooling. My setup is easy to cool. I've got enough air flow that the bulbs are just warm to the touch. It's easy to see that the output exceeds standard HO levels, especially on the SA's (which I just swapped out for a Fiji Purple to take a look).