What was your biggest mistake with your aquarium?

If I could turn back the clock I would have passed on getting the skimmer and just got the R/O Unit instead first. Though Organics would have been in the system, it would have been much easier to remove nitrates and organics instead of adding phosphates and nitrates to my system.

 

Sun Corals - beautiful, but very high maintainance.

 

Putting Xenia in my tank. It is a weed that takes over but I learned a little trick yesterday. I am now moving my euphyllia's closer to it. Ha Ha Ha now try and spread like wild fire.

 

Anemone. I will never have another unless it is a anem specific tank.

 

My 2nd biggest mistake was putting a mandarin goby in my tank without any realistic idea of what was needed for him to survive. That was in the days before 3reef.

 

mine was not setting up my first 3 tanks where they could get natural sunlight. now my 2 tanks get some direct sunlight in the summer and loads of sunlight in the winter months. the coral growth has increased by 30% or more. it makes a huge difference. also IMO natural light makes for the best viewing of the tank.

 

Buying a couple of golden pilotfish for my 150 without researching. Didn't know they get to be about 4 feet.

 

I held onto my PC lighting waaaay to long. Now I need to get my fuge upto snuff.

 

My sump is much too small. My tank is too close to a wall. My tank is not large enough, either.

 

Adding a powerhead wayyyyy to late after starting the tank. Waterflow is important for keeping bad stuff from building up in low flow areas.