M58 Ballast humming

[segraves1]

had my 250W MH M58 Ballast and 6500K bulb up and running for about two weeks now........today I finally got the hood built and mounted everything and I noticed that the ballast is really humming "a lot" (seems to be more than it used to.....)

what things would cause a ballast to hum more/less.....wire gauge/temp/mounting/etc.?

[davejnz]

First off,what kind of 6500k bulb is it?

[dakar]

Is the balllast a magnetic core/coil type or electronic? The magnetics do tend to vibrate a little bit. You can secure it to a piece of wood or use rubber grommets to make 'shock mounts' to help reduce any noise.

[jerryc]

The best thing for a open ballast is to go to a electrical supply or
home depot and get a pull box 4*4 or 6*6 metal box.
bolt the ballast to the bottom. I like to use a hard rubber between the
ballast and the can.
You will need a cupola of cord clamps to get the electrical cord and supply
in and out.

[segraves1]

thanks guys.....

yeah it is a standard M58 mag "open ballast".....the bulb is a 6500 Iwaski (sp?)

right now it is mounted directly to the wood hood...I'll try some rubber....

[dakar]

Great choice on the bulb :p

[davejnz]

I agree with Dakar,Iwasaki is one of the best halides out there for growth IME.If you can get your hands on a 22.5uF capacitor,it'll really drive that Iwasaki bulb the way its capable of.See this thread
http://www.captivereefing.com/showthread.php?t=2699

[segraves1]

yeah I'm running it off of a 22.5uF cap already (thats what HelloLights sent with the ballast to begin with....).....

I'm really happy with how much light I'm getting........the macros, zoanthids, and star polups are really open and looking good (250Watts over a 20gal is WAYYYYYYYYYYYYY overkill but I am going to buy a 150gal when I go to work this summer so I didnt want to waste money on a 175Watt now only to buy 250Watts later........)....


the only down side I see is the micro is growing like crazy (don't have a skimmer on this 20gal (again....didn't want to buy something for this and then turn around and buy again this summer)....have to clean the glass almost every other day.....the hermits like it though....

[dakar]

Did you manage to isolate the ballast to reduce the vibrations that were causing the 'humming' noise?

BTW, in reality you aren't overlighting your 20g, a 250w Iwasaki at 12" water depth would be comparable in Lux to natural sunlight at 15-20' NSW, give or take a bit. I have all the Lux values for the 'sakis around here somewhere, I'll try to dig them all up and put together a chart we can all reference.

So your microalgae problem will eventually balance itself out as the system matures and the nutrient uptake is increased, though a skimmer of some sort would help remove the excess nutrients a little quicker.

[davejnz]

Seagraves,i prefer to add snails/clanup crew in small numbers as algae growth increases.For your glass/diatom algae,you can't go wrong with those Turbo snails.They're better diatom eaters than Astreas and can lift themselves back up when they fall to the sand so your hermit crabs don't kill them.In a 20gal tank though,a couple 5gal waterchanges and the use of activated carbon in the sump/external power filter really helps to lower the dissolved organics in hte tank.However,it also greatly increases the water clarity so it might be a good idea to shade your tank from that MH with eggcrate and a few sheets of window screen.Remove 1 sheet per week and you should be set.