Designing a large tank (210 gallon) (Metal Halide Lights)

[falcondob]

I have been lurking for a month or two and this really is a great group of people.

I have a 45 gallon hex that has been running about 3 months and is doing very well. I will post a picture soon.

I was about to purchase a 200 gal tank, but I work for SBC and with the merger with AT&T my job is unstable right now and I am going to wait. I will use this time to design what it will be like.

So with that in mind, my first subject is lights. I saw a 210 gallon tank with Metal Halide lamps for sale. My questions are:

(1) When buying used equipment, I understand that aquarium lighting can still be "working" and not really be doing it's job. In metal halides, is it the lamps, the ballast, or both?
(2) How do you test for being "used up"?
(3) If any element needs to be replaced, what are the do's and dont's?
(4) Is it necessary to supplement the Halides with CF or VHO?

Thanks in advance.

PS: Is there a meeting held in San Antonio?

[::pete::]

Welcome!!

As for the meeting there is one coming up in Austin February 19th. If you look on the front/home page there is an announcement as well as a link to a .pdf file with all the information you will need ... so please join us!!

As for checking used equiptment the lighting is kind of taking their word for it, replacing do and dont is a hard one to answer without specifics and for supplementation its not "necessary" but helpful and all depends on the setup.

I hope that helps a little ...

[alexwolf]

Wow!!! All tough questions:

1) If the lighting is working, then everything is fine. If its not doing its job, then its the bulbs. They could be old and not producing the spectrums necessary.
2) Really, you dont. Maybe someone else will jump in with some advice on old bulb testing, but not me!
3) Figure on replacing the bulbs anyways. Chances are you will see a combination of colors that you like, and the ones you got arent them! Its really all personal preference.
4) Again, personal prefrence. I think PC are sort of getting phased out with the new HO T5's that are available. I personally like the blue look, so I go with 20k's with T-5 actinic supplement. There are some spectrums that VHO offer that the MH do not, such as 450nm but that, if i remember correctly, is primarily used for anemone's to feed.

March meeting is in San Antonio at my house on the Northwest Side! HTH!


Alex

[Polkster13]

Welcome to the club.

First on the lighting question. No you do not need to replace the ballast unless it is unsafe (bad wiring, burn marks, fan doesn't work - if there is one, and so forth) but you may need to replace the bulbs. You will need to find out how old they are. In other words, how many hours have the bulbs been on. This will only be a guesstimate from the seller but it will give you an idea. For MH bulbs, I have been told that on a 10 to 12 hour on cycle, to replace the bulbs every 6 months. Some people run theirs for longer periods before replacing them. Note this will only be needed if you are keeping things like Tridica Clams, Corals that require brigt lights and so forth. If you are going to keep a fish only tank with some live rock, then you don't need MH lights. MH lights are very intense and they also generate a lot of heat. You may also want to look into the new T-5 bulbs. A lot of people using MH bulbs also have actinic supplement bulbs that come on before and go out after the MH. This way the MH are on for a shorter period of time. For instance, the actinics come on at 8 AM and go off and 10 PM. The MH come on at 11 AM and go off at 6 PM. This is just an example and not a light regiment receipe.

When replacing MH bulbs it is very important to NOT TOUCH the glass of the bulb. If you leave oils or residue from your hand on the bulb, after it fires up it will get very hot and the residue can cause th bulb to fail (or explode). If you accidently touch the buld, wipe it off with a clean rag.

Our next meeting is here in Austin and the March meeting I believe will be in SA. Check the meeting schedule to see when and where the next meeting will be held at.

[falcondob]

Thanks for the quick post. That is great! I live on the NW side at Bandera and 1604. Where are you from there?
John

[alexwolf]

Babcock and Prue, right around the corner from you!

[NaCl_H2O]

Welcome to MAAST! Here is a stab at some answers

(1) When buying used equipment, I understand that aquarium lighting can still be "working" and not really be doing it's job. In metal halides, is it the lamps, the ballast, or both?

Mostly the lamps, they have an operating "Life". They may still be functioning, but their output degrades to the point of being detremental to the tank inhabitants. Depending on the bulb "temperature" and manufacturer, that's typically from 9-18 months. Ballasts are more of a widcard. If they are working you are probably OK, but try to determine the age - if over 5 years they are probably a risk.

(2) How do you test for being "used up"?

Simplest is replace them per the mfg specs. You can borrow a light (PAR) meter, but those aren't eal common among reefers

(3) If any element needs to be replaced, what are the do's and dont's?

Not sure I understand this question? There is a complex list of ballast/bulb compatibilities for metal halides. Somebody posted a link to a chart once, maybe they will respond to this post?

(4) Is it necessary to supplement the Halides with CF or VHO?

Most reefers do, but mostly for appearance. VHA, PC, or T5 actinics mixed with halides gives a much better look and shows the color of the corals better.

- Steve

P.S. Good luck with the merger results!

[falcondob]

Thanks to everyone. That pretty much covers my questions on lights (for now) :-D

I am going to start a new thread on the next item. I really dislike long threads.
John

[Jenn]

Gosh, the NW gang just keep growing! Welcome to MAAST John and hope all goes well with the merger. I have been in that position before and it stinks!

[falcondob]

Thanks Jenn. I am glad to be here. I am now a fully addicted reefer!