Fish geek math: Petite water exchanges. Easy.

Don't you just love water exchanges? Seems like I'm one of those weirdos who does. I am not even sure what the specific reason is...but I like doing them. It's like a "feel-good, tank bonding" ritual thingy for me, I suppose. I dunno. A habit.

Not everyone shares my geeky enthusiasm about 'em.

I talk to a lot of hobbyists daily, and it's practically a given that they'll complain about doing water exchanges as much as we like to complain about stuff like taxes, our cable bill, or whatever.

Seriously. What makes us dislike something that's so beneficial for our fishes?

Maybe it's the whole dogma of the thing...or the way "the books" made it seem like this major thing- like an oil change on our car or something.

Since our “infant days” in the hobby, we’ve had it drilled into our collective heads to perform "regular water exchanges" on our aquariums. It’s one of those hobby “facts of life” that we just can’t avoid. We know that they're beneficial...

I think it's because of the Draconian demands to perform them that water exchanges tend to be viewed by many hobbyists as a "necessary evil"; a practice that we put off or begrudgingly embrace on a random, periodic basis.

Many hobbyists will do the occasional 10%-25% water exchange once a month, maybe even once every couple of months, or even less often (oh, the horror!)!

Okay, it's 2016, a new year- I say to defer those other, tired resolutions (quitting smoking, working towards world peace, eating more healthy, excercise, blah, blah, blah) and shoot for something more important: Developing an easy aquarium husbandry habit!

5% Twice A Week. Yeah, really!

As you've heard ad nauseum for years, a primary benefit of the water exchange is the dissolution of dissolved organics in the water. The accumulation of this stuff can lead to significant degradation of your tank’s water quality over time. Many anomalous “crashes” have their roots in lax maintenance practices.

The key to preventing this kind of stuff is, of course, dilution. If done consistently, regular small water exchanges can help dilute organic wastes before they ever have an opportunity to accumulate in your system. 


My recommendation for an easy-to-accomplish, super-beneficial water change regimen is to perform two 5% water changes per week



Seriously, this is a lot easier to accomplish than you might think.

Before you pummel me with "Jungle Pods", think about it. It’s not that big of a commitment.  

You probably spend as much time checking your Twitter feed each day (well, at least I do!). We’re talking, like, five percent of your tank volume (that’s only 5 gallons in a 100 gallon tank, or just 2.5 gallons in a 50 gallon tank), performed on, say, Wednesday and Sunday. By following this routine, your aquarium is never more than 3 days from the next water exchange! Super easy.

You've got this.

However scary it sounds, it’s not a daunting task, by any means.

In fact, you can perform an efficient water exchange in less than10 minutes on a good-sized tank (Trust me here- I timed it!). That's like a long TV commercial break!

Using decidedly “low tech” methods, you can accomplish a water exchange easily with dry hands!  When I say “low tech”- I mean it! We’re talking about a length of flexible plastic hose, or a plastic pitcher- nothing more! We're just exchanging some water. 

The other side benefit of frequent small water changes is that you are more “involved” with your tank on a rather “intimate” level, on a more frequent basis. (as if that is possible!) You'll see subtle changes. You'll recognize trends, good and bad- and be able to correct bad ones before they become potential problems.

'Cause you're already in there!

Or, maybe you'll see that clutch of cichlid fry that you'd otherwise overlook if you weren't in there...Stuff like that.

And, since you’re making these little water exchanges, why not use the opportunity to inspect or replace chemical filtration media, clean/replace mechanical filter pads, etc? Little stuff.

Again, you're already there, right?


You'll notice differences: Your fishes will display brighter colors, and seem more alert and active than you’ve seen them before!  Spawning activity often occurs after small water exchanges for some species. I've seen it dozens of times before.

 Water parameters will remain more stable, problematic algae, if present, will begin to disappear from your system, and your tank will take on a certain...something- often a visual clarity or "sparkle" that will make you sort of pause and say, "Wow!"

With this many collateral benefits, why would you blow off small frequent water exchanges? Just do 'em.

Till next time…

Stay Wet.

Scott Fellman

Scott Fellman
Scott Fellman


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