undergravel filter

Hi,
I have a tank that I set up with an under gravel filter. My question is this; If I now take out the under gravel filter will this upset the balance of the tank?

 

How long has this tank been set up for?

 

Not exactly sure but more than 8 months! I have 2 clowns a serpent star and a cleaner shrimp living well in there shrimp has molted twice! No corals yet. I have like 60lbs of live rock a canister(flu-val 405) filter a nice skimmer(remora w/mag 3)plus a bio wheel hang on and a aqua clear 110.I also have a nice wave maker set up with 4 pumps I just don't like all the tubes in the back from the under gravel looks unnatural! I want to remove it and add some sand on top of my crushed coral substrate! hope this helps!!

 

What kind of animals have you got in the tank at the moment? Either way, if you don't mind a bit of a cloudy mess and dealing with a mini cycle afterwards, I would remove the undergravel filter. If you add sand on top of your crushed coral, you could easily smother and kill the bacteria that is in your crushed coral so if you're going to do that, do it a little at a time. Personally, I would remove the crushed coral and replace it all with sand because crushed coral traps detritus which could lead to nitrate issues down the road if you don't keep it clean. If you decide to replace the crushed coral with sand, you will also want to do this a little at a time so that you don't remove all of your bacteria at once when you remove the crushed coral.

 

I had crushed coral in my first reef setup. I drained the tank to about 1 inch above the CC, grabbed my shop vac and sucked all of the CC out. I then placed my sand in, added some seachem "stability" and away I went with adding my livestock back in the tank. I had a 2 day ammonia spike and that was it. I would turn my skimmer up on "kill" though