Halogen lighting question

[Liz]

Hi all,
Haven't posted in a while but am after a bit of advice. Hope you can help.

I have an arcadia series 3 pendant light system with 2 x 30watt acintics and 2 x 150watt double ended metal halides with an Rx7s lamp cap.

I need to replace all my bulbs but am dreading the cost of the halides (last time I looked they were going to cost me £45 each!)

So I have a plan but am not sure if it will work. Can I use 150watt halogen bulbs for security lights? Are they the same thing or are marine aquarium lights special in any way to warrant the enormous additional costs.

I don't want to kill my corals trying to cut corners. But I'd quite like to save some money.

Any help or advice welcome.

Thanks
Liz

[ccCapt]

Halogen bulbs are the wrong color spectrum. You can look around, but I think most halogens are in the 3500K-4700K spectrum. You really don't want to use anything less than 6500K.

[Edmonton Eskimo]

halogen bulbs don't run on a ballast so they are not even compatable with a mh setup.

[seaham358]

there is no Cheap way out, you need to buy the correct bulbs.. I would change out the actinic after you change out the MH, no need to do them all at once..
how old are the bulbs

[Liz]

Thanks for the replies.

Sorry Edmonton Eskimo, I don't understand your post. I thought halogen bulbs were MH? And I don't have a ballast, least not that I'm aware of. Though I'm not entirely sure what a ballast is in the context of marine tanks. I conceed that I know little more about lighting other than the system I currently run, which works. My motto: Unless it's broke I don't fix it.
Sorry - me being un-clued. I've only had my marine tank for a little over a year now and so though I've done a lot of research I confess I only know about the stuff I have in my tank and any planned upgrades or additions. I think there is that much to learn I could speand a lifetime doing it and still fall short of expert. Fascinating subject.

Anyway, I did some more research after asking this forum. Discovered that its unlikely that i'm going to be able to find the right K values. I now understand that if i don't get the right K value my tank is either going to look very yellow or very cold and none of that is good for the corals or my viewing pleasure. So I've ordered all the correct replacements and will add them one at a time over a period of months.

Thanks for all your help.
The bulbs were there when I had the tank (bought from a friend who was moving to Italy) I haven't replaced them yet (its been on my to do list) and I'm uncertain how old they were before (the tank being established for 2 yrs before that). So they could be 3 years old! (I'm guessing 2 though)
I know I should have replaced them earlier but it seems daft to when they still work nothing is suffering and they're that expensive.

Thanks again
Liz