Carroll, with dual 250w MH's on a 55, you can keep anything, softeis, LPS, SPS, acros, clams, everything.
Provided you have then at the right deapth and acclimated to the lights, and also the correct water paraments and filtration.
The MH lights wont effect your acrylic, HQI light might if you dont have a qualified pendent with UV glass covers, but for the light to "wear down the tank" that would take decades upon decades....
I have dual 250w Mogul 14k hamilton bulbs on my 55g with dual 110w Actinics to simulate dusk/dawn
snipe, like said above, PC lights dont penetrate and they also lose PAr and spectrum fast, while VHO will "die out" on the sides of the bulb and concentrate all of the light to the middle, on a smaller tank PC lights wont have a problem withe low light, but VHO will because the light that is...
Many people like Caulerpa, i personaly dont, Caulerpa has the possiblility to do "sexual" this is when the plant releases all of the nutrients it has taken in, back into the water, most of the time causing a crash.
Alot more people use Cheatomorphia, Cheato will not go sexual, and is a bit plain...
In my room i have a 34g brute tank where i mix fresh RO/di water (i recomend extremely, also an essential) with my salt water and let the water "age" then everyweek i just take out 5g of water and siphon 5g out of the tank and add the other 5g's,
with the agged water i can have water incase of...
okm, Clownfish are very easy fish to keep, as long as you have non toxic water levels and good salinity they will live.
Anemones on the other hadn are very hard to take care of, they ened very stable and mature tanks (7 months about) and need very high lighing, on a 25g PC lighting is sufficient...
with that light i would say you dould keep polyping soft corals, 260w of PV light isnt very much on a 90g tank, 90g tanks are tall, and PC lights dont penetrate through the water far enough, all your corals will need to be on top, and PC lights arent very good for larger tanks, VHO lights are...
its not realy good to go by WPG, it all depends on the type of light you are using, 20WPG of NO lights( normal output lights) will not even be as good as 4WPG as MH (metal halide lights)
what lights are you using, PC, VHO, T5, T12, MH?
the calcium is kinda low for normal alk lvls, we need the alk lvl to determin if the calcium is actualy in line with alk or outa whack. calcium should be 400 or so
nope harmless, that is a Bristtle worm, they are a very good additiong to a cleaning crew, and will quickly dispose of any uneaten foods or carcases. it looks like a fire worm , but only for the fact that its organ line looks blue, but is actualy brownish.
IMO no, as long as you can keep heat stable, and acclimate the corals to the light over a period of time.
i know a guy who has 1 400HQI over a 30g frag tank, and another guy with 2 400w mogul over a 40g breeder.