Statistics --Lies, Damn Lies, or Worthless?

For the heck of it, I took out my fish journel and then used a spreadsheet to record each major fish or invert that I bought (not small snails or hermits), the date I bought it, and the day it died. I was thinking that things were getting worse in my tank and that the statistics would show it.

I have a lot of data -- I've bought 55 creatures over the past 19 months. The average lifespan is 99 days, but the median lifespan is 33 days, mainly because 14 (25%) lasted a week or less. I've had 11 creatures live longer than 200 days. Currently, my longest-lived fish is a Decorated Firefish that I've had over 400 days, since November 2005.

There are no clear trends. There were two spikes in the death statistics and I'm pretty sure I know what caused each. Things are not especially any worse or better now than they have been for the past year.

So, I don't think that I am a bad hobbiest. I know many of you have had fish or inverts for years and years. But, how long does your average resident last?

 

well in the beginning... lol. i lost a lot of fish withing a month. but since i got my pygmy angel i have not had a problem with loss except the BTA that you all read about and i lost a goby of some sort. so in the past year i have lost four significant fish and inverts. but the angel is going on like almost 4 years. the false per i have is going on a couple of months. and the red coris wrasse and blue damsel are going on for two years.

 

go the firefish i bought mine december 2005 he has lasted better than any others ,if the tank started to go bad(hasnt happened in 2 years) im taking them out, straight to fish store for keeping i cant kill anymore fish.

but to do the stats i probably sound horrible at my new chosen hobby but no deaths besides collapsed tank 100% death and strange clownfish disease (which the lfs owned up and gave me credit )is the only thing within 1 whole year 8) so im going to stick to gobies highest sucess rate i havent murdered any..lol

 

There's a number of problems with keeping statistics like this. However, here is the biggest one:

Unless all of your animals were bred in a tank, you don't have a clue how old it is. Additionally, different species have different lifespans in the wild. To give you an example, my favorite mantis has a shorter lifespan than many other species of mantis. I still prefer peacocks knowing this.

Here's another problem. Some species are more subject to predation than others. Putting it into your tank will probably help it live longer. I have a friend with an 18 year old clown. Other fish can be stressed by putting it into your tank and their lifespan might be shorter. This is why it is sooooo important to fully understand the needs of animals before we purchase them.

Regardless, I still recommend keeping track of all purchases.