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GH, KH, pH, and Peat

2023 Views 7 Replies 4 Participants Last post by  plantbrain
I am really glad to have found this site, looks like there is lots of advice here to be had. After stumbling over an un-set-up 135 g for two years, I am finally ready to get it going (my wife said, "use it or lose it).

Before I get started there are a couple of issues that I need some help with.

I have some concern about the hardness of my water. I can use either untreated water or water which has been treated with a softener. The untreated water gH = 13.8 and KH = 11, the water from the softener is gH = <1 and the same KH = 11. The question is which water source should I use? What other problems do you think I will run into with water this hard?

For the substrate I am going to go with fluorite. Given the hardness of my water, should I put a fine layer of peat on the bottom? What effect will peat have on my CO2 levels (i.e. the CO2/KH chart)?

1. Tank water volume: 135 gallon
2. Tank lighting: IceCap w/ 3ea. 5’ VHO URI AquaSun 460 watts, 3.12 w/gal
3. Tank filtration: Trickle
4. Tank substrate: Fluorite
5. Do you CO2? Yes, Automatic w/ Controller

Thanks for your help, any advice is appreciated.
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The majority of plants will do fine in your hard water. My tap water is very similar to yours and except for some Rotala magenta (which reportedly prefers soft to moderate hardness) and Ludwigia 'cuba', everything grows well for me. And even the 'cuba' is coming along once I moved it to a different tank (same tap water, though).

Adding peat will acidify your water (lower the pH), but I don't think it affects the hardness any. Same with injecting CO2 into water, it'll lower the pH but the hardness will remain.

Your trickle filter may cause you to outgas some CO2, but you can compensate by upping the amount you inject (the penalty being the need to refill your CO2 tank more often).

Other than that your setup looks good. Have fun setting up your tank! :)
I would remove the trickle portion and add a bag filter.

Raise the level in the over flow up higher so there is less splash into the prefilter, that is where you will lose CO2 mainly.

You can use some sponge material in the sump if you wish.

The small amount of peat will not influence water chemistry, it will influence the substrate and cycling.
Add some fresh mulm from a LFS, a buddy's tank etc, make sure you do this. Rinse the Flourite 3x and that's all.

Read up and get a decent method to make large water changes easy on yourself.

I've never had much issue with tap water being hard, I prefer that over the soft water. One or two plants might act funny, but do not use the water softener Tap.

Once you have the CO2 set well, check its AM and PM level to make sure it checks out.

Keep the probe/Reactor etc in the sump, set it for 25-30ppm of CO2.
Have the returns spray down along the back wall into the plants along their base.

Plant heavy from the start, this is important.

This will get you going pretty well and nutrients/dosing routines will be easy to maintain from here.

Tom Barr
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One reason that the hard water concerns me is that I plan to use Glossostigma extensively and from what I read they do not like hard water. When references state that a plant does not like hard water, do they mean high GH and/or high KH?
Does anybody have any experience with Matrix from Sachem? I was planning to use water from R.O. but later I found that I would have to put away for 100liters of prepared water, 300liters! And there is another problem, I live in an apartment, so I can't actually use this water - have to put it away.

Any suggestions? Or is it still better to stick to R.O. water? Water parameters in my area are: ph 7.5; kH 11 and most important: NO3 20mg/l. All this values are to high for planted aquariums! Help please, what to do?

R.O., Matrix from Sachem or sth. else? Another thing, I was planning to change every week 1/4 of water (100l of 400l aquarium). Will this be to little?
Gloss did great at a GH of 25 and a KJH of 10, I think whoever told you it does better or worse is well ......quite clueless and helping to foster a myth.

I've consistently grown it for many years in hardwater, so have most folks like most so called softwater plants.

The only reason you need to soften water is for a few softwater fish, it's not for the plants at all.

Tom Barr
Thanks for the Glosso info Tom, that is one concern I can cross of my list. The Tropica database lists hardness tolerance for Glosso as soft and that is what got me going.

I would still like to use the faucet water which has been softened by a water softener. Really for maintenance reasons, no calcium buildup, etc. Do you see any problem using water that has been softened (i.e. salt content, maybe)?
It's a PITA and cost you $ and makes water changes a hassle. Knock yourself out:) I'll pass.

Tom Barr
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