Moving to MH !

[Yanir34]

They are different sizes. The E40 bulb will work fine on E39 sockets, but E39 bulbs won't always work perfectly on E40 sockets. I changed my E40 socket on my Giesemann Spectra and now I use either types of bulbs (E39 or E40) with the E39 socket. Please contact Dave at Hamilton. That's where I've got my E39 from and it's relatively easy to change them.

Thanks mate

 

[Yanir34]

AFAICT e39 is the same as e40.
Ex39 is an issue. E39 in an ex39 socket won' t contact the center so no light.
Ex39 in an e39 base will but may extend out more. There are other differences apparently.

What is the difference between E39 and EX39 base?

EX39 Mogul Base The EX39 base has a longer tip base. EX39 based bulbs can be used in fixtures with standard E39 or EX39 sockets. Bulbs with EX39 bases have protective shields so can be used in either open or closed fixtures. SHOP FOR EX39 BULBS E39 Mogul Base Bulbs with E39 base will only...

www.bulbamerica.com

E39 and e40 are interchangeable afaict

Thank you

 

[oreo54]

Thank you

Yea I should have checked deeper .

The E26 and E27 are usually interchangeable, as are the E39 and E40, although less so; although there is only a 1 mm difference in thread outside diameter, there is a small difference in pitch; an E40 cap will often fit in an E39 holder but not the other way around.

Sorry .

 

[Yanir34]

That’s a 21 inch deep tank, you should be good with 250 watt halides. LED bars would be best for fill light, unless you mix in some T5. I like reef brite bars for their spread. Orphek bars will have higher par but a narrower spread. I’ve also heard good things about quanta bars lately.
Most people run 20k halides these days. I’ve used Reef Brite and Hamilton bulbs with good results. I’m sure giesmann will grow sticks. I would work the halides up to 6 or 8 hours a day and run the LEDs for 10 or 11 hours a day.

It seems that 2 bulbs of 400w is fast too powerful for my tank . I'm switching now to 2 bulbs of 250w

 

[Yanir34]

What is the recommended high to 2*250w MH above my tank ?
again , the dimensions of my tank :
140 cm long
70 cm wide
55 cm high

 

[minus9]

What is the recommended high to 2*250w MH above my tank ?
again , the dimensions of my tank :
140 cm long
70 cm wide
55 cm high

Probably around 30 to 32 cm above the water is fine.

 

[Yanir34]

Probably around 30 to 32 cm above the water is fine.

With 2 bulbs of 250w , right ?
because it seems to be that the 400w is way too much powerful .
I added 5 sps frags last week.
3 of them is at the floor of the tank, and very happy with very good polyp extension.
the 2 frags the was glued to the rocks got bleached at at their tips.
I'm sure that it is because of the high of my tank (55 cm , water line is at 50 cm), and the 400w bulbs.

 

[minus9]

With 2 bulbs of 250w , right ?
because it seems to be that the 400w is way too much powerful .
I added 5 sps frags last week.
3 of them is at the floor of the tank, and very happy with very good polyp extension.
the 2 frags the was glued to the rocks got bleached at at their tips.
I'm sure that it is because of the high of my tank (55 cm , water line is at 50 cm), and the 400w bulbs.

Yes, 250w. I'm using two 250w Hamilton 14k bulbs at 12" (33 cm?) above the water in about 15" of water without issue. Remember, when increasing lighting intensity, you need to increase flow as well and make sure you have measurable nutrient levels.

 

[A. grandis]

Yes, about 30cm above the water surface. Place a small fan blowing air parallel to the water surface, not into it, between the fixture/reflectors an water surface if you can, not critical. That will help to cut the heat transfer from fixture to water. 30cm will be the way to go there.
Please post pics of the Acros and grow some for me, you guys!!! Cheers!