Two quick questions
 

1. Can I run an air pump in a marine tank to add oxygen? I always worry there's not enough and have had one given so thought i may as well use it

2. Decided to attack aptasia with lemon juice as they are growing faster than I can kill them now. Is there any risks I should be aware of before commencing?

i would think an air pump is no problem
but i would like to share that i solved my aptasia problem with two two pep shrimp.

1. yes its up to you. there are many ways of putting more oxegen into the water, and using an airpump is one of the most unattractive ways, IMO. For me, I use the airpump to oxegenate the water that I will use for a water change

2. I've read about people using lemon juice, but the citric acid does something to the alk and ph of your water... Better to wait for more knowledgeable people who know this stuff.

1. You don't need it but point returns/powerheads toward the surface to promote surface movement (increases oxygen).
2. It will raise calcium rapidly so make sure this is a large tank or else trouble, but i would use Joe's Juice Aptasia Remover (safer)

I use a kalkwasser/Lemon Juice/Hot Water mix to kill aptasia. Works good. I have never seen any adverse affects on my livestock. I have used this method a few time over the course of the last 6 months and everything tests good.

If you have a skimmer, their is little need for an extra airstone... you can over-oxygenate SW...

For the Aiptasia problem, I use hot lemon juice in a hypodermic needle. I stab the little sucker and pump him up.. looks like a bad boob job ...then he pops!

Do not see a problem with the first one to add air, most people dont want one in their display tank though. Going to have to left some one else assit you with the 2ed question though.

[QUOTE][i]<a href=showthread.php?s=&postid=11519375#post11519375 target=_blank>Originally posted</a> by MinibowMatt [/i]
[B]If you have a skimmer, their is little need for an extra airstone... you can over-oxygenate SW...
[/B][/QUOTE]

Can you elaborate on over-oxygenating SW?

I use kalkwasser for aiptasia.
Works great!

I have a copperband butterfly in my tank as soon as the aiptasia was gone he went right for the flake food I feed mt other fish he also eats brine. It's the only fish I own that I bought from the LFS I wanted to see one eat prepared food before I bought it.