View Full Version : acropora in a 20 gallon with 70w MH

07-19-2011, 11:26 AM
the title basically says it. I have a choice between high or long, If that matters. I'm looking to grow out some frags. 14K bulb and a koralia evo. also, what supplements should I dose and how much? will purple tech and nano-reef A and B cut it? thanks for the advice.

07-19-2011, 11:45 AM
For a frag tank, you'd probably want to go with the long instead of the tall. More real estate that way. As for the supplements, it all depends on the demand. What kind of corals, how many, ect... I would think frequent water changes with that size tank should be sufficient.

07-19-2011, 11:53 AM
cool. so 70 watts is enough?

07-19-2011, 12:10 PM
Should be ok as a grow out tank. Some of the other MH users might be able to chime in with their experience with the 20L and MH as far as wattage/coral selection.

07-19-2011, 12:50 PM
hope so. I just want them to grow well, and 150 almost seemed like overkill. I'm sure someone could contradict that, though.

07-22-2011, 07:46 AM
70 watt MH is good enough for a 20L, anything more and you risk bleaching the corals. They will stay bleach until they adjust to the lighting. I would use 6500k bulb if your just using it to grow out corals. You can always put a couple T-5 actinics on it to enhance the color. You will get a lot of growth with the 6500k vs the 14k bulb. For the dosing part, I would just do water changes every week with a good brand of salt.

07-22-2011, 09:09 AM
6500K would be bluer, correct?

07-22-2011, 09:12 AM
6500K is more yellow-white...the higher the number the more blue light you get.

07-22-2011, 09:55 AM
oh, too bad, I like the blue. doesn't matter thuogh, as logn as I get good growth. thanks for the help, I don't know much about this stuff

07-22-2011, 11:07 AM
As a rule of thumb as stated above

Lower K= Growth
Higher K= Coloration

The plan for my grow out tank is going to be about 12-16 inches deep 2 tier 150-200g tide pool style. Top tier for SPS, lower for LPS. I plan to put a 250w 6.5-10k MH on a rail and moving back and forth over the whole thing. Once the corals get to a proper size I am going to move them into the 20k holding system, probably in the range of 50-100g to color them up before selling/moving into the display. I know people who have 400w MH on their frag tanks 12 inches off the water. Yeah if you put a frag from a tank that was under PC into a 400w system without acclimating them to the light they will get fried, if you acclimate them properly they will be fine. Think of how much par that alot of these corals get in the wild from the sun.