# Soft water plants in hard water



## Avalon (Mar 7, 2005)

I have very hard water ( KH:13/GH:18 ), and while I'm able to grow the great majority of plants well, I have problems with soft water plants such as Rotalla macrandra, Ludwigia pantanal, etc. (ie, "super" soft water plants). They don't achieve the proper size. Take for example my L. pantanal: it's growing quickly, but it's an 1" in diameter, tops! It's also at the surface now, under direct light, and the leaves look like needles rather than thin leaves. The stems are kind of sickly looking.

To the point: Would a substrate such as Florabase or ADA (Amazonia) be beneficial to the aforementioned plants using my hard water? I am not willing to lug in R/O water for a 75g tank. I currently use Seachem's Onyx & Flourite.

75g
216w T5
Tons of CO2
EI method
weekly water change


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## chiahead (Dec 18, 2004)

Hi Avalon. My tap water is very similar to yours and I had the same problems growing soft water plants. I just recently switched my 80 gallon to ADA substrate. Although I am not using 100% tap I have been using 50% tap 50% R.O. So far with the ADA it has kept the Kh around 3 and the Gh around 5. This may be a temporary thing, but I think the acidity of the substrate is more important for soft water plants. I think your problem now is your onyx substrate. It leaks minerals and raises the Kh to the point where soft water plants have issues. I will let you know how the soft water plants I am trying to grow do after the settle in a while.

Plants I am growing:
Tonina-manaus, Belem, Fluivatilis, Uaepes
Eriocaulon Cinerum, Setecum
Rotala Macradra Regular and Narrow leaf
Ludwigia Inclinata ver Cuba, and Pantannal


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## plantbrain (Jan 23, 2004)

My plants(same species) do not have issues in onyx.

Soft water for these seems to help, but they will still grow in hard water, just not as big and fat.

I do not think it has to do with the substrate, it's more the KH, pH perhaps.

Many critters/plants etc have an optimal range their enzymes operate at, so the pH/Temp/concentration of the nutrients etc all play a role in speed of uptake(which is controled by enzymes on the plant's cell surface) and thus growth.

Most plants are fine with a wide range, a few are not for some reason, this would be a good place to look though.

Regards, 
Tom Barr

www.BarrReport.com


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