PDA

View Full Version : pc vs mh vs etc.



nanopodreefer
12-17-2006, 08:23 AM
ok so I edited my post, here are my questions...

does 100 watts mh lighting = 100 watt pc lighting, if not is there some sortof ratio? mh/pc

is the uv light that I will encounter from looking at my tank, (light coming through glass) harmful? or is it the same as normal sunlight outside when I look around? Is it worse or not as bad?

Thanks.

lReef lKeeper
12-17-2006, 12:44 PM
mh penetrate deeper. i have halides on my tanks and i will NEVER again use anything else !! you cant really measure the lighting for a marine tank by watts per gallon. metal halides are a much more intense light than PC, T5, or VHO. you would really need a lighting meter ( i think it is a par meter) to see how much lighting you actually have.

nanopodreefer
12-18-2006, 04:02 AM
I revised my questions....bump.... :)

George
12-18-2006, 11:05 AM
Unfortunately, there's almost no way to generalize this and it comes down to questions of livestock needs (and future plans) and aesthetic preferences.

100w MH doesn't equal another 100w MH either, unless the ballasts and the bulbs match. PAR (Photosynthetically Active Radiation) and PUR (Photosynthetically Usable Radiation) can vary even within a bulb spec (i.e. a Hamilton 250w 14K bulb and an XM 250w 14K bulb probably don't have the same ratings). Even with the same bulbs, ballasts can figure into the equation as well. I'm not nearly as familiar with variances in PC lighting as I am with MH lighting, but I'm almost certain similar effects occur.

Take into account the physical nature of the light. MH = point source of intense radiation. PC = elongated source of diffuse radiation.

The only thing I can consistently say is that PC will evenly light your aquarium (assuming your bulb arrangement somewhat closely matches your tank length), but MH will more intensely light your aquarium with fall-off towards the edges. That's speaking X watts PC vs. X watts MH.

The harmful UV light put off by lighting should be blocked by protective glass over your fixture since it's not good for the animals either.

The short answer to your main question is "No", but that wouldn't have been a very polite answer. :)

nanopodreefer
01-07-2007, 08:04 PM
Well after some research, I can see just how elementary my question of 100watt pc = 100 watt mh was, thanks for humoring me guys, but I guess that's what being a newbie is all about :). I have decided on T5's, going to light my 29 tall tank with 4 or 5 24" T5's if I can fit them all inside the hood.

lReef lKeeper
01-07-2007, 09:06 PM
glad to be of assistance. that is one thing i love about this hobby ... helping others with something i know a little about.

nanopodreefer
01-16-2007, 11:00 PM
Ok so after some thought, I had a few questions regarding t5 lighting. Some threads say that you need special european t5 reflectors, does anyone know what these are? does Icecap supply these with their retros? Basically how do I distinguish between the european and the "regular"?

Secondly for you t5 fan's/"experts" out there, I want to compile a t5 checklist that a newbie can work off of. Since too many products out there have discounted rates, by cutting corners, ie: no reflector, etc. Yes t5's are good but you need the best parts to take advantage of the efficiency. A list that a new hobbist can check off to know that their decision for t5's will not be in vain is what i had in mind.

For example
1. t5 bulb
2. single light reflector (no double or quadruple reflectors),
3. type of reflector
4. HO and VHO bulbs
5. ballast brand that will give best results (ie: icecap that can overdrive, etc.)
6. ballast to bulb ratio 1-2, 1-4, etc.
7. ballast location, ie: remote/or in canopy

Your ideas/opinions can help this lsit evolve, thanks

iglowce
01-16-2007, 11:27 PM
how about the solaris LED? u should get those. i cant cuz they are still darn expensive =]

nanopodreefer
01-21-2007, 11:39 AM
this thread is old but i added a new question, see above... bump

NaClFinatic
01-21-2007, 02:23 PM
I dont know what european reflectors are. But make sure you get parabolic reflectors for each individual bulb. This will put the maximum light into your tank. I am planning to buy T5 retrofit equipment (ballasts, reflectors, standoffs, endcaps, and bulbs). Not sure yet if I will get the kits or individual pieces. Sometimes the kit is a little cheaper.

Most people with T5 seem to have an even mix of actinic and daylight bulbs (or some have slightly more daylight). Definitely get the HO t5 (there are some lower output out there also but not as much light). In the HO I will have 4ft bulbs which are 54W bulbs. The NO bulbs are only about half that. I don't know of any T5 with more output. For my 90g reef I will use 6 or 8 54W bulbs, which will take all of the space above the tank.

I do not know which brands are best. Most of the retrofit ballasts power two bulbs. And I think all of the T5 ballasts are electronic, so they are reasonably compact and minimal heat. Still I though I would mount mine on the back side of my canopy just so they arent as exposed to the salt, arent adding to the heat as much, and out of the way since the bulbs will take up so much space underneath.

I also plan to have a small fan or two that I could manually turn on if heat builds up. In warmer conditions it may just be able to be plugged in with the daytime light timer to keep the tank cooler.

A question I have with the lights is on using a lens. Would a lens make a significant impact on the amount or quality of light that reaces the tank? I wouldn't just buy some piece of acryllic at the hardware store because this stuff probably doesn't have the best optic properties, but for one of the commerical fixtures (Tek) you can buy a lens separately. Buy acrylic Lens 8X54W for T5 Tek Lights Here! (http://www.specialty-lights.com/904230.html) I could mount that in my hood so it slides out easy and could be quickly wipped down a couple times a week. I just see the individual bulbs as being a little more work to clean throughly and be careful not to break them.

NaClFinatic
01-21-2007, 02:32 PM
Actually I just looked and do see some ballasts that do 4x54w. I guess I was planning on the 2 because there isn't much price difference and so only 3 bulbs per ballast will give me more control over the lights.

iglowce
01-21-2007, 03:45 PM
i have MH.. unless u have LED system, i suggest complimenting your MH wt PC/T5.. but again it all depends on the livestock you plan to have..