Metal Halides

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.

Holokai

Aquarium Advice Regular
Joined
Apr 15, 2004
Messages
98
Location
Kingman, Az
I did a quick search on the topic, but I was unable to determine the answer to my question - Would two 250w MH lamps be too much for a planted FW tank? I'm converting from SW to FW, and want a heavily planted tank, I figure the more light the better, right? But I am new to planted FW tanks. Thanks for any advice.

- Chris
 
MH's are used for growing plants, but I think they use a lower Kelvin rated bulb...something in the 4300 range I believe. What size tank? I would think tho, that no matter what size it is, with 2 250's you can grow a jungle. 8) Just be sure to have them high enough over the water and/or good ventilation so it doesn't overheat your water.
 
Why yes, a jungle IS my intention ;)
Ventilation is handled by 4 very LARGE fans.. I can place my hand an inch away from the bulb and it's cooler than room temperature 8) I bet I'd still get a nice sun tan though ;) I do have access to about 100 6500k Bulbs, so we'll see about that too. Thanks for the info.

I read somewhere on here that the more light you have, the more CO2 you need? whats taht all about? and would I need an ungodly amount?
 
when you hit 2 watts per gallon, you really need to start injecting CO2. Plants need 3 things: light, CO2 and food. All three have to be in balance, or you have problems. With strong light and good food (i.e. fertilizing), but no CO2, you'll grow plants and wicked amounts of algae. Without CO2 the plants can't grow fast enough to use up all the ferts, so the algae takes over that job.

You still haven't mentioned the size of your tank, but I'm assuming it's pretty good size. You'll have to get the parts for a pressurized CO2 setup. A 5-10pound CO2 cylinder, a regulator (get a Milwaukee All in One), and something to diffuse the CO2 into the water.
 
Whoops

Sorry, I meant to add that it is a 75 gallon tank.

So these CO2 parts, what cost am I looking at? The reason I am leaving SW is cost... I'll look up some DIY plans if there are any. thanks.

- Chris
 
Whoo.... 500W on a 75G tank (6.6 wpg) is a heck of a lot for a planted tank. People seldom exceed 5 wpg. You may have a lot of algae as a result... Also, the fish might be a little stressed by the light level.

And yes, with light that high, plants will grow extremely fast, and will need a lot of CO2.
 
You really need to go with a pressurized CO2 system with that kind of light. You should be able to put together a decent system for less than $150, one-time expense. then 10-15 bucks for refills on your co2, never more frequntly than 6 months. All my tanks last 8 months or more.

You'll need more like 5-6 two liter diy setups to keep up with a 75 gallon, and that's with light ranges I'm familiar with. you'll soon spend the $150 on sugar alone. At least within a year I would say.

7.7 wpg is so far out of any range I've ever heard of, I don't even know what to say (other than use SPF 45 sunscreen). Any chance you could just use one of the Halides? I have a 45 gallon tank lit with a 175 halide. You would likely have the same issue I do of unbalanced lighting. My halide is to the left of center on this tank, leaving a bright area to the left, and a darker area to the right. I just use this as different zones for planting, have some lower light plants on the right side, high light to the left.
Just some things to consider.
 
7.7 is low for a Reef Tank, which is what this was. My only other choice due to price constraints is NO fluorescent bulbs. I can wire up 240w of those, if that would be better than using the 500w MH (this is so damned frustrating!!! I spent so much moeny to get these bright lights!!!! )

Would 240w of NO lights be decent enough? work's out to 3.2 wpg.

Thanks - Chris
 
Would 240w of NO lights be decent enough? work's out to 3.2 wpg.
Plenty, you could grow almost any plant you want.
7.7 is low for a Reef Tank, which is what this was.

Wow, just shows how little I know about SW, reefs especially!
 
Pretty much any fish that likes to eat and poop alot and doesn't feed on plants, which means cichlids are out unfortunately. Clown loaches would definitely be up there on the list.

-Dan
 
Holokai,

Don't let it be frustrating. Use the MHs when you get your next reef tank. No need to get rid of them!

Corvus is right, though, about the CO2. Bite the bullet like we all did :( and get the pressurized CO2 system. Its potential for delivering CO2 to the system is hundreds of times higher than with DIY. DIYs usually deliver about 1 bubble every 5-20 seconds (or so), while a DIY can deliver dozens of bubbles per second (though this would mean you would run out of CO2 pretty fast). With CO2 it can get more expensive--a solenoid is almost certainly a necessity, as it turns on and off the CO2 in the morning and night for when you're out. A pH regulator (~$90-$110 shipped) is a second possibility, as it maintains a stable pH for the fish, and controls the solenoid. I've gotten on fine w/o the pH regulator, but I highly recommend the solenoid.
 
Back
Top Bottom