What was your biggest mistake with your aquarium?

Scott how did you do to solve the ventilation issues for your tank?

 

2nd that one

 

Only using one thermometer..
Kept cranking my heater up thinking water temp was 81 when it was really 10-11 degrees hotter due to a faulty digital thermometer. Now I have 3.

 

I have 3 6" holes in the side of the house now. One is incoming air for fresh air in the winter and the other two are for exhaust and air off the chillers condenser.
I have been looking into a Energy Recovery Ventaliator for the help in the winter because my heater runs all the time when I start bringing in 10 degree air and blow it in the fishroom. :-/

 

Check out these guys for ERV's: UltimateAir RecoupAerator®::Learn More! I gave this serious consideration and may be forced to go this route yet. I was looking at ventilation for just the tank and fish closet so I would have run into problems with it adding heat to the tank in the winter. On a plus note, they were willing to explicitly honor their warranty even for use around the reef tank. Since you are using this for the whole room, you sholdn't have quite the same issues. The in-line exhaust fan only cost me a few hundred while an ERV is several thousand plus installation costs.

 

Too many to mention here.....I think it would probably have to be impulse. I didn't know the first year or two of salt would be so complicated. I just liked the way the corals and colors looked.
Followed buy aquarium size. I could of saved major bucks by buying a drilled tank also....lost a couple grand on soaked carpets and dead livestock, etc, etc, etc.
Research, even buying books before livestock.

 

Biggest mistakes:
1) Thinking a smaller tank would be easier to learn on
2) Using Tap Water
3) Trusting that my LFS was selling me RO/DI water
4) Trusting house sitter to take care of the tank while on vacation
5) Afraid to mod my tank

After 2 years, I'm finally coming around... thanks to you guys on this forum :-[

 

Moving to quickly at first.

 

That's scary. You'd like to think that you could take such things for granted but I guess that most folks buying RO/DI from the LFS don't have a TDS meter to verify that you're getting what you're paying for.

 

Yah, no kidding! I finally broke down and got an RO system put in and added on a 2-stage DI system. It has a nice TDS meter that allows me to test on both the inbound and outbound connections.

I find that it is more exensive to make and mix my own water, but well worth it! I'm also hoping that the salt mix I'm using (Reef Crystals) will allow me to stop (or minimize) the amount of addatives I need to add to the water.