Snowflake Moray Eel

Question
I have a set up in a 2foot tank, I have live rock (2x 2kg & 1 x 1kg) plus (1x2kg enviro rock) in it & I added a plant which took to the live rock to try to cut down on the Nitrate levels.  My levels are very high, could it be from having such a small tank for my eel, which is about 40cm.  The weed is flourishing although some of it is tinged with red.  Or could it be that I am feeding him every day & therefore he would have more body waste.  I was told adding extra movement to the water would change it, I have done this for a fortnight but it is still apparent.  My filter is a canister filter 700lt, & added a power head 350lt an hour.  Can you please advise what steps I could take to rectify this problem.  I do general cleaning once a month with a gravel cleaner.  I also remove his body waste everyday.  Also is a seahorse a compatible tank mate?  Do you reccommend a sand base when I establish my 4 foot tank. If not what do you suggest as a full setup for my snowflake moray eel?

Answer
that tank is seriously wayyyy too small for the eel, they need tanks that are a minimum of 150gallons as they are messy fish. how can extra movement in the water help remove his waste? also if you think that the eel won't eat a sea horse your having a laugh!!

i wish that you fucking idiots would do some reserch before you buy fish, its because of the thousands of numpties like you the oceans are in trouble, the fish you buy come straight out of the sea and you put them in a tank thats not even suitable for goldfish.