[pandacory]

What parameter readings or changes indicate it is time to do a water change?

Also, how do you prep your top off water?

I will continue to do my weekly testing, and will be adding kh testing to the regiment, but i dont want to just blindly change the water any more. I have a feeling that that is a waste of water, and may disturb the stability of the system.

 

[Hoppy]

That depends on how you are lighting and fertilizing the tank. If you don't use CO2, and have low light, you can ignore water changes entirely, just adding enough to make up for evaporation. But, if you have high light intensity, use CO2, and dose non-limiting amounts of all fertilizers, you need to set up a routine water change schedule to avoid building up too much of any of the fertilizers in the water. In between those two scenarios, you have a lot of flexibility with water changes. In any case, other than with non-CO2 tanks, water changes do no harm to either the fish or the plants (assuming you use Prime or equivalent with water changes.)

 

[wkndracer]

Reducing water changes

My two high light injected tanks are kept a little differently than the rest of my tanks but still not scheduled on the changes.
The tap here is crap so a dedicated RO system is used for tank water. Once I gathered a number of tanks together there was a need to manage things better.

Providing for my plants now includes enriched substrate or root tab supplements in all the tanks. The need for water column dosing was reduced when I combined the methods.

Both high techs get the tabs replaced every 90 days.
Currently doing 15ml per day in a trace/Fe mix, more or less, missed is a couple days some weeks here and there.
All other ferts go based on tested levels. WC's as needed.
PO4 and TDS (pen) are monitored as phosphate repeatedly was my offender with levels decreasing over 4-5 days.

Broad range on what the plants do well with gives me wiggle room (imo).
2-5ppm PO4 and 15-30ppm NO3 target. K2SO4 added weekly for 15ppm if I don't do a WC or dose NO3 (which I don't often).

WC is done based on rising TDS readings or the parameters getting hosed up.
Average on these two 75g tanks is a 50%WC once a month.

 

[plantbrain]

I changed 50-70% once a month of these:

Lower light, easier to care for plants, good well fed fish load(which adds ferts).

I can easily do more water changes without issue, but over time, one can easily reduce and watch their tanks without any associated risk.

I'm not sure bragging "I do few water changes" is good advice however.
I think taking good care of the fish and plants is FAR better advice, particularly if you are not seasoned and fairly competent in growing plants and fish care. If anything appeared wrong, water changes.
If you want to stay on top of things really well, frequent large water changes.

This is more proactive and easier than monitoring other things for most folks. Makes everything else much simpler.

 

[wkndracer]

Being the only one posting a reduced change cycle here, I wouldn't call it 'bragging' Tom just answering what I understood the OP's question to be.

 

[plantbrain]

Being the only one posting a reduced change cycle here, I wouldn't call it 'bragging' Tom just answering what I understood the OP's question to be.

Naw........not you, it's many folks that seem to brag about it, do not take this stuff so personally, there is no intent. Some seem to suggest........as if it means they are better aquarist or something. I do not think there's anything that implies better or worse really. If you note, I also made my own bragging of my tanks that get similar water change routines:hihi:
I am as guilty as you here.

With time, many folks can go this route and others can start off with this goal in mind using less light and sediment rich sediments etc........
I think folks can have VERY nice tanks with this type of routine.
Folks should look at the other things that enhance the goals and look at water changes objectively.

If avoidance of water change is the primary goal, and also reduced labor(why else would they avoid them to begin with if that(labor) was not the real case??), then we'd all should be telling folks to use the non CO2 method, but many do not say anything about non CO2 to folks typically.

Testing does not reduce labor. It adds to it. I do not need to test and do monthly water changes, but have a few caveats. The light(lower vs more) good CO2 management, and sediment based ferts+ routine care are more important than testing.

So we can get away with less water changes and..........no testing also.

You are not far off with your own tank, has mud, good CO2, light etc.........reduced modified dosing.........monthly water changes.
I think you could go with no water testing.

 

[zdnet]

If avoidance of water change is the primary goal, and also reduced labor(why else would they avoid them to begin with if that(labor) was not the real case??)

Fresh water is a limited natural resource. Some people try to strike a balance between their hobby and "water footprint". Depending on where they live, some may even have to deal with regional fresh water shortage crisis. Some people have attributed the crisis to rising demand driven by population growth.

Our water bill does not reflect the true cost of the fresh water that we use. From the article "Yet Another 'Footprint' to Worry About: Water":

"In the U.S., water managers in 36 states anticipate shortages by 2013, a General Accounting Office report shows. Last year, Georgia lawmakers tried, unsuccessfully, to move the state's border north so that Georgia could claim part of the Tennessee River."

Places through out the world are having their worst drought in decades. Not just Africa, but China and the States as well.

Testing does not reduce labor. It adds to it.

Testing can reduce labor, unless people are applying a method requiring water change at a pre-determined interval. For example, instead of doing water change every week, people can dip a TDS meter into a tank and decide whether that week's water change can be skipped. If they understand the impact of what they are doing to a tank, they can probably reduce the frequency of water change from once every week to once every 2, 3, 4 weeks, or even longer. Unless people have an automated water change system, the labor reduction can be significant.