Have we been doing aquariums wrong?

[BuzzDaddy21]

On 7/1/2022 at 5:02 AM, Pepere said:

What is the purpose of a water change?

When I got back into the hobby a while back, I thought a bunch of water changes was stupid and still do (The so-called experts say you must do water changes, I could go on a long rant about this 😜) Once I changed my tanks over, I don`t do water changes per say and I`m happy with the results and that's the only thing that matters.     

[gardenman]

In theory, water changes replace trace elements and assorted whatnots in the water that get used up. Is it true? Eh, maybe. Many modern fish foods contain those trace elements and in some cases in excessive quantities. What happens with excess trace elements that the fish don't absorb? Depending on the trace element they may be voided from the fish in its urine/feces, much like excess vitamin C gets urinated away by humans. Those now free trace elements then end up back in the water column. It's entirely possible that a very well-fed tank could have more trace elements available before a water change than afterward. 

I tend not to do water changes unless something has gone drastically wrong. I just top off evaporation and go on. Between fish food and plant food any lacking trace elements are likely replaced as quickly as they're lost. Having said that, I did a 90% water change yesterday when my 30 high crashed. A fish had died in the tangle of jungle val and gone unnoticed and uneaten and caused an ammonia spike. The fish were in trouble and changing the water and finding/removing the dead fish fixed the issue. Everyone's happy and back to normal today. Water changes have their place, but are they absolutely necessary on a daily/weekly basis? Probably not. They certainly aren't necessary for me. Given the issues with water resources, fewer water changes may be better.

Edited July 1, 2022 by gardenman

[Torrey]

ORD🥰

I love responsible discussions!