automatic water change, via plants

[MaloK]

The nutrient uptake is controlled by root transport that is influenced by water itself, also microorganism play another role in the plant trying to keep the best internal nutrient level.

But I'm positive that animal hormones, some medicines, organic compounds produce certain types of pollutants that are not readily utilized by plants and will persist in the water.

 

[MuddyWaters]

This is really interesting! First, I'm amazed at 30 dang feet of pothos!!! LOL- I've got 4 plants coming out of my 75 gallon- pothos and something else I can't remember but saw online that they're good for growing out of a tank. They grow pretty well, but nothing like that- of course, I've only had them in there for 8 months or so.

I've never thought about whether plants take the water and everything else or just what they need, but how would they filter out stuff they don't want? Also, someone mentioned the herbicides, and that's a good point.

To me, it's all in your experience. As has been clearly stated by several, there are so many things one just can't know, so if your experience is showing that your fish are healthy with the regimen you describe over time, then it's working.

However, like many things in the hobby, it is likely a one-off based on the specific conditions you have. It's kind of like planting the same kind of plant in 2 different tanks using the same water, same fertilizer, same water parameters, same lighting and the plant grows like crazy in one tank and will hardly grow at all in the other. Something is different, but Lord knows what it is...

I like changing the water in my tanks (yes, I'm weird), so I'd keep doing it, but hey man, if it's working drive on!

I wonder if the TDS rises as the water level lowers? I know it would from evaporation, but if you could determine how much it would rise from the evaporation and see if you get even more from the rest of the water that is pulled into the plants, then they must be leaving something behind. I guess TDS wouldn't account for everything that's in the water, though.

 

[MaloK]

Everything dissolved that is not conductive, TDS meters don't measure or detect.

That's a lot of things.

 

[Aqua67]

I think it is important to replace minerals that have been taken up by the plants and fish, therefore remineralized RO water is what I use in all of my aquariums. I rely on my TDS meter to tell me when it is time to test my water, saving me time. Yes, evaporation will cause the TDS to rise as there is less volume in the aquarium, but TDS measures all dissolved solids which include fish waste, nitrogen, nitrites, ammonia, calcium, magnesium, any water conditioners, fertilizers, etc. When my TDS readings increase by 30-40ppm, that is when I test the water to see if a water change is necessary.

 

[Magnum Man]

I have the minerals to add back, but am assuming the foods, I'm feeding contain much of what is really needed, as I've never remineralized in the year, that I've been using RO...

I have had a few mature fish die, but it seems really random, nothing related to age in the tank, or by species, but it could be caused by mineral shortage, but doesn't seem like it, as my tanks are heavily stocked, seems like if there was a vital mineral shortage, it would be more apparent

 

[MaloK]

I have the minerals to add back, but am assuming the foods, I'm feeding contain much of what is really needed, as I've never remineralized in the year, that I've been using RO...

I have had a few mature fish die, but it seems really random, nothing related to age in the tank, or by species, but it could be caused by mineral shortage, but doesn't seem like it, as my tanks are heavily stocked, seems like if there was a vital mineral shortage, it would be more apparent

Do you test the water from time to time to see how your minerals fluctuates.

I can imagine, with your setup, it must be draining the minerals from the water. Or fish food has more minerals than I think.

I use small doses of fertilizer and the plant uptake in calcium carbonate immediately rise.

 

[Magnum Man]

I have the test tools, but honestly don't have the time to go looking for a problem, when everything seems to be running well...

I do think a good quality food ( and I use a large variety ) does include much of what the fish needs, nutritionally...

I'm also due to change my RO filters, so I suspect the hardness could be starting to creep up on that as well...

 

[MaloK]

Do you have a TDS tester ? At least you can have a rapid general idea with this.

I would not let anything go under 50 ppm even for the very soft water fish.

 

[Magnum Man]

I have 2 professional level TDS testers for boiler water at work, and a cheap ( found unreliable ) one here for my tanks... been meaning to bring my older one home, as I don't need two at work