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I use groundwater to fill my aquarium. I don't have test kits, but I sent my water to a university lab for a test.
Here's the result

pH: 7.10
TDS: 535 ppm
KMnO4: 8.44 ppm
Bicarbonate: 170.8 ppm HCO3
Total Hardness: 238.0 ppm CaCO3
Ca: 53.6 ppm
Mg: 25.2 ppm
Cl: 134.9 ppm
Fe: 0 ppm
SiO2: 0 ppm
Mn: 0.1 ppm
NO2: 0.5 ppm
NO3: 28.0 ppm
SO4: 65.0 ppm

Now from my research, it would seem that Total Hardness here is KH? And by the general rule that 1 dKH is around 17 ppm, my water is really hard? And based on the condition of the water, for a heavily planted tank, what ferts should I be dosing?
 

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I have some questions about the report but for general this is what I see.
Pretty hard alkaline water. I might go further and guess that it is underground water pump in an area that has large limestone deposits. Perhaps the center of the US? But certainly could be from other places.
Hard and some would object to that but I have lived in hard water areas much of the time and it is just something that I like and deal with as a small problem. I like using a water softener for my tap water as it helps in a number of ways. But I use the raw water for my fish and plant tanks.
The major point I might be confused or missing on the info is the CL ( chlorine) content. They may be using a different method or I'm forgetting my water treatment training? I cut and copied this from an online site:
The EPA requires treated tap water to have a detectable level of chlorine to help prevent contamination. The allowable chlorine levels in drinking water (up to 4 parts per million) pose “no known or expected health risk [including] an adequate margin of safety.”Mar 30, 2010
With a reading of 134 PPM, it would say you have more than thirty times the legal limit of chlorine! Some checking needed on that? I think the allowable limits are 3-10 PPM so something is not right with that part.

But that parts in not really the critical factor for dosing N, P and K plus some micros. I would suggest just starting with one of the dosing plans and then adapt it as you see how things are going. I started with the EI dosing method but there are several plans.
 

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Your dKH is very high. The Ca/Mg levels are spot on. Cl was measured as free chlorine levels?

.1 ppm or 100 ppb Manganese is a good level which might be a good indicator that some more micro nutrients are in the water already.

Your K is the only thing that is not there but you have KMnO4 or Potassium permanganate in your water. Maybe dose 10 to 15 K ppm to be sure you have K. Even at higher K is OK. P personally do not go lower than 30 ppm.

For Fe or Iron, you'll need to dose .2 to as .5 ppm or higher and just try to prevent it from bottoming out.
 

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Perhaps the center of the US?
Nope, halfway around the world, I'm in southeast asia.

The allowable chlorine levels in drinking water (up to 4 parts per million) pose “no known or expected health risk [including] an adequate margin of safety.”Mar 30, 2010
With a reading of 134 PPM, it would say you have more than thirty times the legal limit of chlorine!
This this count even when I don't drink the groundwater? I use an RO system.

Cl was measured as free chlorine levels?
I have no idea, honestly. They also provided a reading for "Aggressive CO2" which read 0 ppm

Would my high dKH affect my plants/fishes in any way? Is it the cause for my plants not growing too well?
 

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Without knowing how the levels are being measured it is an open question on the chlorine. For the way we measure chlorine, it would be pretty quick death for any fish, etc. and even treating with a product like Prime would be a question as it is designed to remove the normal amount with some slack figured in for safety. But if we were speaking the same testing, it would not cover that much. That is what makes me think there is a difference in the reporting.
Is this groundwater that has been treated or just a simple source without treatment. I have not run across naturally occurring chlorine at that level but then again, I've never drilled/tested or used a well in that area. Maybe it is a real reading and natural or pretty aggressive treatment or pollution of some type.
Your water is hard but then it is not what I would consider unworkable as mine is quite a bit harder at 300+. There are plants which grow in all the water around the world so there are those who really like the hard water.
Rather than say it is the cause of low plant performance, I might look more toward nutrients that are not provided at high enough levels, lighting or CO2 as the cause.
 

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Potassium permanganate is not something desirable in aquarium water, except for temporary use to kill parasites. Your water looks like it has been treated and isn't straight from the well. If my tap water looked like that I would use RO water, and add a GH Booster, like SeaChem Equilibrium to restore the needed minerals. I would also find a good aquarium GH, KH, pH, and perhaps NO2/NO3 set of test kits for routine use. I would not use a chemical lab's water test results without a lot more studying to find out exactly what they are testing for, and how their results can be converted to the standard test kit results we normally use.
 
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