Concerns about using RO water.

[smileandnod]

Hi.

Having spent some time searching this site for info on using RO, I've found a wealth of very useful info. Thanks to all who have posted.

Hoever, I still have some concerns about using RO water for my fish, and I would like someone to help put my mind at rest.

As far as I understand it, I cannot use straight RO, as this does not contain any number of minerals and metals that the fish need in order to survive. It would kill off my plants pretty quickly too.

So I have to mix it with tap water. This I am fine with, as it effectively dilutes the tap water, so that some content is retained through the water. Also, as I understand it, the dilution should be quite simple. Mix one part tap with 3 parts RO, and you should have a hardness 1/4 of the tap water.

So my concern is this. In order to get my extremely hard (19 dkh, and 10 dgh) water down to a KH of about 5, I need to add 1/2 a litre of tap water to 9 1/2 litres of RO. My concern is that this will not provide enough of the mineral content that the fish require, and does not seem to add up right.

Or am I missing the point, that the tiny amount of hardness disolved into the RO will provide everything required.
(My mixed GH by the way is about 4, and the PH in the tank is stable at 7).

Thanks.

Ian.

 

[farm41]

The apistos are a softwater fish, they thrive in mineral depleted water. It is only a small amount of minerals that they need, and they will get that with your at probably 1/10th tap or less.

 

[skwelch]

relax, things will be fine only mixing small amounts of tap with your RO
even for the apistos that require very soft water

from my experience and this goes for most fish, the most important thing after acclimatising the fish slowly to your water chemistry is to make sure you make plenty of water changes with water that has very similar parameters to that in your tank

ie always make up the same amount of water adding the same amount of tap with RO

i have very hard tap water like you and always mix 90% RO with 10% tap and my apisto's seem to thrive


..........also, you know what hard water is good for too
african cichlids, hmmmmm malawis

 

[fishgeek]

i agree that your dilutions dont seem to fit the theory
a 5% solution should be a lot less hard than your readings
or perhaps your hardnes readings from the tap are inaccurate

what test means are you using?

I have been playing about with water parameters and trying to get an understanding of these things since i got my combi meter for christmas , still find it difficult to understand

assuming that your measurements are made with the same kit there may be some discrepancy in the readings at either end of the scale

There was a very informative link ., can for the life of me remeber where on hardness etc that i just read recently perhaps someone else has a better memory
Andrew

 

[M0oN]

I'd say it largely depends on their age, after 3 months old they shouldn't have problems in water with that little minerals, but at a younger age I'd recommend starting them off slightly harder to get proper growth...

 

[fishboy20]

it might be helpful to know which species you are dealing with as well. different species come from different environments.you should start out by keeping the species that exist in wide range of water quality values. would seem the logical choice to me (ex: agassizi, borellii, cacatuoides,ets.). pH values do affect some Apisto's sex ratio as well, most notably borellii and eunotus. but this is secondary in most species of Apistogramma. R/O water is great for apistos but not always needed, (unless your talking elizabethae, mendezi, etc.) start out easy and then work on the specialized species.

 

[smileandnod]

Thanks for the replys folks.

First I will stop worrying.

I have a pair of Inca50, who seem very happy, and show no signs of stress, or any other problems. I guess they are about 6 months old now, and are constantly showing and displaying to each other. (have been for about a month now, so I'm not holding my breath waiting for fry anymore).
I mix my water well before I need it, and always have about 30 litres ready to use.
I change about 20% of the water twice a week.

My test kit is a liquid type. Fill the testube, add drops till it changes colour.
As I rinse my test tube with tap water :roll: , I guess there could be some contamination or residue left behind, giving false readings.

So I am going to switch to the paper strip type test. I guess consistency is far more important than actual values.

This is my first foray into RO water, and altering water chemistry, so I am a little apprehensive.

Thanks again.

Ian.

 

[farm41]

For Inca50 I would only use a 20:1 RO to tap ratio, they like it real soft, and add some peat too. Mine spawned at PH5.9, and EC <80µS.

You could just use straight RO for the next few water changes to get things down quicker, the inca won't mind getting soft real fast, in fact they will love it. I add just enough tap to keep the water buffered.

 

[Peter Lovett1]

Hi Ian,

Sorry that I have not posted did not realize it was you.

As you live in bucks I would suggest you go with just the RO and not mix it at all your RO should be about 15ppm and your tap about 360ppm.

Also most of the trace elements that your fish need they will get from there food. Also small amount from food and excrement will dissolve in the RO water.

The problem will be with the plants in your tank they will suffer, but by adding peat extract or black water extract redress the balance redress the balance should help. Also the Inca will love it.

Also the Inca you have where spawned in a ph 6.5 and a TDS reading of 120ppm and do so ever 6 weeks.

Sometimes you just have to wait and keep your finger crossed.

I have been trying for the last month to get 3 F1 female to spawn with a wild male with no success.

But I got some A. sp. â€Âfresa†two weeks ago never saw them for that time came into the fish room on Sunday to see the male fresa sitting at the front of the tank and the female in her cave with a clutch of eggs. Though they had spawned quite a few times for the person I got them from.