# Should I use RO water



## SalvadorNL (8 Apr 2013)

hello UKAPS,

I am a new member an have posted a short introduction in the new members section.
In short I am in the process of setting up a hi-tech planted community tank in a Fluval Roma 200.But in the past have always done lo-tech tanks.
Now I have a question about the hard water in Cambridge (uk) and was hoping you guys can help me out.
When I measured the Kh and Gh of my tap water they were Kh: 13 and Gh: 20 (German dH) Although Cambridge Water claims the water has a Kh of 17... (I used nutrafin master test kit to test).
This is pretty hard water, and due to the limestone, there is also a very high Ca content. Is this too hard?

I know a considerable amount about chemistry, but do not know what to do. I have read and understood that most fish can handle hard water. But also read that the advised hardness is a Kh of 4-8 and a Gh of 5-10. Could I and or should I mix up my tap water with RO water to half the values, will I be losing much other minerals, or would the dry fert dosing replenish those?

Another question.
If I do mix with RO water, would a wonder shell be good? I have used wonder shells in the past with good success (lo-tech), and Ca or Mg does not dissolve out of the shell unless the concentration in the water drops below a certain point (at least what I've read). I know Seachem Replenish does a similar thing, but adds back calcium as well, which is not really essential in Cambridge Water. And has no long term buffering/releasing capacity + costs more.

Apologies for long story,

Thanks for any help,

S


----------



## ceg4048 (8 Apr 2013)

Hello,
		Here is a tank with KH 15+ and GH 26+
I would only go through this trouble if the type of fish being kept are soft water, or if the tank is going to be filled with Tonina or the handful of plants that actually care about soft water. Instead of the tedium of RO, it would be better to worry about keeping the tank as immaculately clean as possible by doing large frequent water changes as well as regular scrubbing and preening.





Cheers,


----------



## tubamanandy (8 Apr 2013)

What are those lovely plants at the centre rear and front left ?


----------



## SalvadorNL (8 Apr 2013)

ceg4048 said:


> Hello,
> 
> Here is a tank with KH 15+ and GH 26+
> 
> ...


 
Hi Ceg,

That is some nice plants indeed! Looks great! I've seen pictures of that tank in other threads as well (before I decided to buy stuff). I am going to use your method of flow from back to front. Does it effect the direction the fish school in? Are they more directed towards the back or front of the aquarium, or does the flow direction not make a difference?

Good to know that I don't need to fiddle with any of my tap water. It only caused trouble in the past.
I do wish to keep tetra's but I believe they should be able to adept, however, since my local LFS does use RO water, I ought to introduce them real slow.

Another question,
Do you, or can you even do gravel cleaning in a tank like that?

Cheers,
S


----------



## ceg4048 (8 Apr 2013)

Hi,
   I haven't really noticed that much effect on schooling. It seemed like the behavior was modified more by the obstacles like plants and hardscape than anything else.

I'm constantly doing gravel cleaning, but of course it's more difficult to do when there are carpet plants. For larger plants, you will almost always be trimming and replanting the tops, or pulling up the bottom portions, discarding and replacing them with the tops. So one really has to get in there and clean. Roots get unwieldy and blocks flow. I use a simple arrangement of connecting some filter tubing to a filter intake mesh. Using a pump or siphon you can then just stick the inlet directly into the sediment and move it around. That works fine unless you are using sand or very find sediment. Swords and crypts will take over the substrate unless they are uprooted and trimmed at the roots.

In a CO2 tank, removing fallen or damaged leaves and keeping everything trimmed and neat is a big deal, even if you're going for a jungle look, the plant mass will block flow. Even with ferns, the roots tend to grow in messy where they are attached to hardscape, so that should be managed as well. I never really worry about all those other parameters, unless, as I mentioned, if there are specialist fish.

Cheers,


----------



## ceg4048 (9 Apr 2013)

tubamanandy said:


> What are those lovely plants at the centre rear and front left ?


Hi,
  The large centrepiece bush is Limnophilia aromatica. The other to the left is Ludwigia Inclinata Var. Verticillata 'Cuba'.

Cheers,


----------



## tubamanandy (9 Apr 2013)

Thanks - very impressive plants


----------



## SalvadorNL (9 Apr 2013)

Thanks Ceg,

Very helpful information!

Cheers


----------

