Low tech, with ferts. Avoiding water changes.

[LancsRick]

My tanks are really starting to mature now and I'm learning a lot from trying to perfect health details rather than worrying about shapes at the moment. One thing that I've been been mulling over is water change frequency. I know some people are religious about them, whilst others never ever do them. My current approach is a 10% change when doing filter maintenance every 1 or 2 months, and that's about it. The tanks seem to be doing really well like this, so I'm wary of doing regular water changes since "if it ain't broke, don't fix it". The exception of course is when I have a problem.

So, in short, if dosing ferts, can a pretty much zero water change approach still be viable long term? Or is my doomsday slowly approaching?

 

[stu_]

Out of curiosity, what are you dosing (lean EI ? )and how often?

 

[Alastair]

I went months and months on my previous set up with zero water changes whilst dosing lean and using potting soil capped. I then started doing occasional ten percents to bring tds down purely for the shrimp I had introduced. otherwise I wouldn't have bothered much. just skip a week of dosing now
and then

 

[dw1305]

Hi all,

So, in short, if dosing ferts, can a pretty much zero water change approach still be viable long term? Or is my doomsday slowly approaching?

The TDS will rise over time.

Personally I'm keen on keeping up with some water changes, I'm fairly convinced that long term they are essential for tank health, although I'm not quite sure why. One reason may be that my water changes "trickle feed" Daphnia from the water butts, other reasons may be to do with dilution of hormones and organic carbon compounds.

I think that some of the problems that Diana Walstad suffered with her Rainbow fish was to do with her lack of water changes.

Have a look at: <350L low tech tank algae problems | UK Aquatic Plant Society> it has a lot more detail.

cheers Darrel

 

[LancsRick]

Cheers. I'll just do the minimum for the time being to keep on top of the TDS and see how it goes. Did a 15% change today actually as I checked and it was a bit high. I try to keep it around 250-300 usually.

 

[plantbrain]

I've gone a couple of years without water changes using a modification of EI rates, but you get fairly good at watching one species that tends to be dominate, and dose based on it's condition.
Low tech approaches are inherently less work, which is the goal and few, if any waters are needed, or beneficial.

But they require a trade off that many cannot handle: patience.

TDS should stay about the same within a 100ppm.

Plant trimmings export TDS! So does cleaning the filter etc.

 

[LancsRick]

Cheers plantbrain. I'm quite happy with the patience side, if/when I have a lifestyle where I can commit to high-tech levels of effort then I'll give them a go, otherwise my (main) tanks will all stay low tech.

As you say, I think I'm going to end up maintaining water changes purely for the shrimp, since they're the only thing potentially at risk from TDS raising. That said, since I dose weekly I expect it varies a reasonable amount during the week regardless.