Lighting DIY mars conversion. Questions and answers here.

[BigSm0]

Well the light works ok for veg and flower. The problem is definitely the transplant. It's like being picked up, slapped in the face and thrown in an ice cold bathtub first thing in the morning. You shocked the plants for sure. Especially at an older age which Sort of makes it worse. If your comparing the mars to the cobs you may be very disappointed. Cob growth is much much better especially with the ones you chose. If you were to keep the mars stock i would use it as supplemental lighting only and not a sole source.

 

[Hygrade]

Thank you so much for answering. im glad that I didnt pick the wrong cobs. Im gonna germ new seeds and start over.

 

[BigSm0]

I'd keep them going. Even if you pull an oz it's worth the little extra time.

 

[theRealDespotic]

I wish I would've found this thread sooner! I cannibalized a mars II 1200 to make a DIY cob unit. I bought 4 CXB3590 72v 3500k CD bin. The trouble I had was getting a good reading on the fv and amperage of the drivers. My mars fixture had 9 drivers in it. After chatting with growmau and a supra on RIU I decided that the drivers should be safe for my cobs so I hooked them up finally. I've run them 2 days straight without any excessive heat or failures so I'm hoping it's going smoothly but I wish I could've got some sensible results from my crappy multimeter.
I've got the monster hanging over a nice little garden of autos right now. Hopefully they produce as well as I've been anticipating.

 

[BigSm0]

The drivers didn't have any markings? Most that I have seen are rated for 88v. The only real test is if it works it is within specs and if not then it's not. No harm to the cobs or drivers either way.

 

[biglee]

Hi guys. Thank you for allowing me to post here. Be prepared, I am total noob. First time posting here.

I am pretty sure the problem isn't the lighting but i just need to rule it out.

This is my 3rd go, I have had 2 successful attempts using blurple mars in the past. This time around I am experiencing very slow growth. The 2 sour crack are 29 days old and like 4 inches tall in 1l pots. They are going into flower so I guess I messed up this time. I transplanted them out of foxfarm ocean forest because the growth was so slow i thought it could be a problem with Foxfarm OF. I transplanted into cocoloco/kind soil. 2 weeks after transplanting them, they haven't had much new growth. Very little vertical growth. I suppose my transplant technique could of been sloppy and may be the cause of this. However, it could also maybe be the lighting since Im such a noob. Are these lights ok for veg and flower?

I converted a 400w mars II with (cxa1512 6500k 18v) x 2 and (CXB3590 3000k 72V) x 3

I also converted a 300w mars with (cxa1512 6500k 18v) x 2 and (CXB3590 3000k 72V) x 2

I started the seedlings under the 400w with all lights on at about 36" away. Maybe I should start them under cfls first like I did when i used blurple?

Did you say that they are in 1l pots sounds like you're pots are to small

 

[BigSm0]

Did you say that they are in 1l pots sounds like you're pots are to small

I agree. I think 3 gallon is the minimum. I went from 5's to 7's and finally make it 2 days without watering

 

[Rosco1012]

Whats up everyone! I recently acquired 5, 300w LED lights that I want to convert to COB. They are exactly like GalaxyHydros, but do not have an brand name on them. I have been doing research on building COB grow lights for several months, and have a fair share of understanding of how they work. However, the more I read and the more COBs I look into, the more I am confused on which options will be best for my drivers.
Each light has 2 drivers rated at 80-130v 550a, and another for the two fans. What would be the most bang for my buck on these drivers?
I also have a viparspectra 900W that I will convert eventually, so was hoping to get some advice on that one too. Output voltage 100-140V, current 700-750mA-5W

Thank you in advanced!

 

[BigSm0]

I'd say the citizen 1812's would be your best option. 50v each would put them right in the middle of the drivers capacity. Each cobs should give you around 30w each for $20 per cob.

The viper may be the best upgrade as it's driver is a little larger and more powerful.

There are a bunch of cobs out and I'm sure plenty I'm not familiar with but for the price and performance the citizen are my favorites

 

[Rosco1012]

Thank you BigSm0!

So each of the 300's could be equipped with 4 1812s, and the vipar could squeeze 8? Would you recommend the 1812s for the vipar as well?