2x 250 mh over a 50 gallon?
- Thread starter joshl
- Start date
I have 2 250W MH's on my 90 about 15 inches above water surface. I have a 6 inch fan at one end blowing on the water surface, temps in the house are 78 in daytime, tank gets to 78.5.
I've also got this all in a canopy, so you may have lower temps if you run open top, with lights suspended or on legs.
I've also got this all in a canopy, so you may have lower temps if you run open top, with lights suspended or on legs.
I had two 250w metal halides on my 55. They were single ended bulbs with a good reflector. The canopy was completly enclosed except for the fan inlet and exits. I used two computer case fans, one blowing in and one blowing out. The bulbs were 8" off the water. I also had a fan blowing over the sump.
You need to give specifics if you want decent advice. Answer Dawgdude's questions and you can get some info you can use. Otherwise, you'll get only generalities and nothing that useful....for example, certain brands of reflectors need more space from the water to the bulb because some are way better than others....too close to the water and you'll fry your corals.
Other factors come into play...what temp do you keep the space the reef is in at? A room kept at 68 degrees could incorporate two 250s better than one kept at 78 degrees for example.
Generalities will get generalities...specifics will get you info you can use.
the lights are m58 ballist that i got from grimreefer with large white hoods/reflectors that i am going to mod down to work for my application i know i am going ot need fans i was thinking maybe a large blowerfan blowing in one end of the canopy i am building for it but it is going ot be in the wall so the fan will be blowing across the lights and water and i will have a another blower fan on the other side pulling the air out and out of the house kinda the way grimreefers is set up the bulbs would be a single end moguel style bulb either one 10k and a 14k or 2 14k havent decided yet on what kind of bulb i am going to use
I would start with the bulbs 18" off the water. Incorporate something that will allow you to raise/lower the lights off the water if needed (chain hanger), and then start with a 4 hour photoperiod, run that for a week, then increase by 1/2 hour each week until you reach 7-8 hours a day and do not go beyond that (not needed by corals). And watch your corals closely during this time for signs of stress.
If your corals are fine at 18" from the bulb to water, and you want to lower the lights, I would lower by no more than 1" at a time, and allow a week inbetween lowerings, and go no lower than 12"-14" off the water. And if by chance your reflectors are Lumenbrights, go no lower than 16" from water to bulb.
Unfortunately, not knowing if you have active heating/cooling in the area or what temperature you keep you house at, it is hard to tell if you will need a chiller or not. Your fans will help, of course.
If you find that with your setup the temps are too high in the tank, then you could consider moving to 175 watt halides. You'd need new ballasts and bulbs, but the reflectors would stay the same.
ok i will start there and i keep the house at 70-72 during the summer-- i cant stand to be hott and the room that would have this tank in it would be about the same and i will enough room to add fans if needed and raise and lower the lights if i need to
thanks for all the info!
thanks for all the info!
A room temp of 70-72 should go a long way towards keeping the tank temps low. You are basically shifting the cooling burden onto your home air conditioner that way. Just make sure you can move the heat from the canopy area out into the room or away fromt he tank itself.
- Messages
- 3,454
- Reaction score
- 0
Wow! Wish I could afford to keep my home at 70 in the summer, lol. I keep mine at 80 and manage to keep my tank at 78.5 with some surface fans. Get some pics of the setup, I'm trying to imagine how bright 500watts of lighting over a 50 gallon is.
- Messages
- 102
- Reaction score
- 0
for reference, I have a 65 gallon with 2x250 and 4 36in T5HO's 4in off the water. I do have a chiller but it has not been running(water is currently 77, room is set at 75).
As soon as my XM's show up, I'll show you 1,000W over a 90.
70-72 house temp is gonna be expensive to maintain.
We run 78 daytime and 76 at night and that's enough to make you cringe opening the power bill.
You need to think of a bail-out plan, if you really intend to maintain 70-72, there's a good chance your A/C will puke out. What are your intentions in the event that happens?
I just built the house we are in, and I promise I spared no expense when it came to the A/C, however I also have several 110v window units stored in the garage just in case.. We've already had an A/C unit nailed by lighting at the previous structure on this lot, took a couple weeks to get it working again. One 5k BTU window unit in a bedroom is one thing, trying to cool a whole house is another.
If you do build a canopy one thing to consider is an opening in the top of the canopy where the bulk of the reflector rests, you can have quite a bit of heat just rise of the top while not getting the light spill that happens with open tops. I am running this now with mine with a AC room around 76 - 77 and the temperature is pretty steady from 78 to 79. I have these cut outs in the canopy that let me put the wood "louvers" back on top during the winter. I am 12" from surface of water to lower surface of the reflector. Good luck.
well to get personal about my power bill it only gets to about 175 during the summer and to be honest my ac has been off fro 2 days and my house hasnt gotten above 73 with the fans running-- i did get the newest style insulation put in we i bought my house and have never had a problem so i think i will be ok...........
well i think i have enough info to start my project
thanks!
well i think i have enough info to start my project
thanks!
wow! what kind of insulation did you use? I just finished this house in january, and have R-30 in the ceiling, and R-25 in the walls and floor. Electric bill still runs $300 or more, but then again we are total electric, and keep RV's plugged in and running for humidity control, so we may not be typical.
A/C unit is 19 SEER Trane with variable speed fan, does a great job in the house, outside temps have been high 90's past few days, with 100% humidity.
A/C unit is 19 SEER Trane with variable speed fan, does a great job in the house, outside temps have been high 90's past few days, with 100% humidity.
it is kinda like the foam insulation but you put it in the attic
but last summer my ac took a poop and i had to get it fixed and that power bill was 300 for teh month of july but ever since then it has not been over 175 with my wife at home all day -- before she lost her job 1 year ago i would run it at 79 during the day until we got home then lower it down to 72-73 but with the kids and her at home i just keep it lower
but last summer my ac took a poop and i had to get it fixed and that power bill was 300 for teh month of july but ever since then it has not been over 175 with my wife at home all day -- before she lost her job 1 year ago i would run it at 79 during the day until we got home then lower it down to 72-73 but with the kids and her at home i just keep it lower
how do you have R-25 insulation in your walls? are your walls 10" thick?
best you can typically do is R-19 in the walls (6" stud cavity) with maybe another 1/2" of polyisocyanurate along the exterior face of the wall.. which yields R-21 at best
unless of course you've got blown in place cellulose insulation in your cavity walls (but I've only seen 3 homes that had that and they were over $1,000,000 and in Charleston...
I'm just sayin'
as far as fans go.. I've found some 6" fans that move 44CF of air/min and are quieter than 20db...
best you can typically do is R-19 in the walls (6" stud cavity) with maybe another 1/2" of polyisocyanurate along the exterior face of the wall.. which yields R-21 at best
unless of course you've got blown in place cellulose insulation in your cavity walls (but I've only seen 3 homes that had that and they were over $1,000,000 and in Charleston...
I'm just sayin'
as far as fans go.. I've found some 6" fans that move 44CF of air/min and are quieter than 20db...
