hard water and nutrient uptake

samc

Member
Joined
28 Oct 2008
Messages
1,381
i have just read an article by amano which suggests that hard water prevents a plants uptaking max nutrients. seeing as i have the hardest water area in the uk (very hard) this may be affecting my plant growth. i have never been able to grow stems to look 'lush' they allways look as if they are missing something, even when double dosing EI. and seeing as stems are fast growers this may be the cause. i was thinking with all the snow about it may be a good idea to stock up on soft clean water

do you guys have any views on this?
 

chump54

Member
Joined
28 May 2008
Messages
511
Location
Thorington, suffolk
Sam... how hard is your water? i'm in suffolk and feels like we have the hardest water in the country :lol:

my water is 28.7 german hardnesses (from local water authority info)

anyway I have been using a mix of RO and tap in my 125l tank because I was concerned about how hard my water is. but in my nano I went for straight tap to test it out. It seems to be fine, no probs other than water marks :crazy: the growth is a lot slower but I'm only using easy carbo in the nano so it's not a straight forward comparison. I have switched to 100% tap on the 125l (2 weeks ago) everything is still growing as it was but it's still very early days.

I'll be interested in other peoples ideas on this too.

Chris
 

samc

Member
Joined
28 Oct 2008
Messages
1,381
thanks for the replies. i thought knowone would have any ideas on this one.

just looked on the online water report and its 16 deg. but then a mile up the road its 21 deg :lol: anyway its pretty high so i am going to try mainly soft water and see if it has any inpact.

other views would be interesting
 

samc

Member
Joined
28 Oct 2008
Messages
1,381
just as a reference, this is a average amano tank with 'hard' water
--------------------------------amanos---------mine
TH ----------------------------50mg/l--------112.8mg/l :wideyed:
NH4 (amonnium)------------0mg/l----------0.5mg/l <---i have ammonia before i start :lol:
NO2--------------------------<0.02mg/l-----0.5mg/l
NO3---------------------------0.0mg/l-------50mg/l :wideyed:

sorry about the dashes. it automatically takes spaces out :lol:
 

dw1305

Expert
Joined
7 Apr 2008
Messages
9,987
Location
nr Bath
Hi all,
Sam your water is horrible, 50mg/l is the maximum legal limit for nitrate in drinking water in the UK.
Your water will definitely limit the availability of P, Mg & Fe to a lot of plants, due to the formation of insoluble compounds (P & Fe), and the unfavourable Mg:Ca ratio. If you want lush plants probably your best bet is to find plants that naturally grow in hard water, as they tend to have adaptations to gather the problematic nutrients in hard water.
cheers Darrel
 

samc

Member
Joined
28 Oct 2008
Messages
1,381
hi darrel :wave: thanks for the reply

i have allways had a slight FE deffiency with my stems so that may well be the cause :thumbup:

i do have an ro unit. but i am on a meter so my uncle uses it for his reef tank and runs me off about 30l when needed so i might get him to do that every couple of weeks and that should help
 

plantbrain

Expert
Joined
2 Aug 2007
Messages
1,946
I do not think the ratio of Mg:Ca has beans to do with plant growth other than above an absolute value for each as limiting nutrient, => Liebig's law. Least that is what all the mineral nutrition experts here say (Dr Bloom, he's down the hall from me at UCD, see Epstein and Bloom for a text on mineral nutrition in higher plants) and practical experience dosing and using hard water. Ratios can build up much higher on soil particles in terrestrial systems as evaporation occurs, this is not an issue in aquatic systems.

I think Amano was referencing specifically to Alkalinity, not pH/GH.
GH has no effect and Ca/Mg are both plant nutrients and even at GH of 25 in Santa Barbara, and a KH or 11, I had little issue growing most species when using CO2.

Here's some tanks I had:

DSCN0195.jpg


DSCN0258.jpg


55gal2resized.jpg


Here's L cuba growing just fien outside in the nasty tap of Davis CA, GH is 14, Mg is 50+ ppm alone...........KH is 18........

hARDWATERCuba.jpg


I agree the water listed is foul, I would not drink it.
I'd use an RO unit and use that.

And in general, if you can reduce the Kh to 5 or less, the easier it is for most plants to grow well.
For most aquatic weeds, hardwater(GH and KH) means more weeds, not less.

for us, it's nicer to have soft water, if we want hard water, we can simply add baking soda or GH booster.
Low KH, moderate to high GH is ideal for all species.

I cut the Davis tap with 60% RO to get this tank full of wimpy softwater species:

resizedcubapantanal1.jpg


So it's still fairly hard.........for both KH and GH.

Results speak more than theory, but I agree in general, lower KH is better, I disagree about GH.
I think it's much more about the KH causing issues, likely with CO2 and carbon allocation in aquatic plants than uptake of specific nutrients being "blocked". Some simple test can show that they are not being blocked.

Advice: get an RO unit, drink that RO water, not the tap.

Regards,
Tom Barr
 
Joined
17 Mar 2012
Messages
1,327
Location
Dorset
I live in a fairly hard water area but thanks to Darrel‘s suggestion I’ve been using rainwater in my two Nano’s. Plants seem to be growing well and no nasty white sediment on the glass and equipment.
 
Top