Ro Woes

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marwil

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HI
would be grateful for any help I am using ro water which is coming out at ph6 and am using dennerle ro remineral quantity as stated on the packaging and it has upped the ph tp 7.6 which is slightly higher than it comes out the tap :twisted:. Any ideas would be very gratefuly recieved as its doing my head in.
Thanks
Mark
 

JamesC

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Pure water by definition doesn't have a pH at all. RO water is pretty close and because it has no buffering capability the pH reading you get is almost meaningless. In theory though pure water would have a pH of 7.0 so any carbonate or bicarbonate that is present in the remineralising agent will push the pH up. If you wanted to compare your two water samples then leave both in a glass for 24 hours and then measure again. This is because tap water often contains dissolved CO2 whereas your RO water most likely won't. CO2 will lower pH.

James
 

marwil

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Hi James
Thanks for the quick reply I just panicked a bit cos all my tropica plants have arrived. Do you think I should get it all filled and up and running and see how it pans out.
Cheers
Mark.
 

chris1004

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Themuleous said:
Yeh I would. Also why not mix the RO with tap to get the desired hardness? Save you a fortune in remineralisation salts :)

Sam
I wouldn't, I mean whats the point? you've just filtered the water to get all the nasties out of it then you go and put some back in!!! As for saving a fortune on remineralising salts that simply isn't true. A 250gram denerele remineral+ for examole is about a tenner and will treat 5000 litres (to kh1 I presume) therefore it is around 0.2p per litrekh or 40p to raise 200litres by 1kh (hardly a fortune in this hobby). If you use the AE gh plus it works out even cheaper. At least with remineraling salts you know whats gone back into the water. A lot depends on your tapwater to start with, how much you want to raise the kh by and how paranoid you are about water quality I suppose.
 

gratts

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Relatively speaking, UK tap water is very good quality so doesn't really contain any 'nasties'. I wouldn't worry about anything like heavy metals, lead etc. Even if there are a couple of molecules bobbing around in your water, there is nowhere near enough to do any harm to anything.
Are you using RO water to reduce the pH and or hardness? If so I'd just do what Them suggested and mix with a ratio of tapwater to whatever pH etc you want. Seems easier and cheaper than messing around with salts which are largely unnecessary IMO!
 

gratts

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That's limescale - just solidified minerals. Probably the same stuff you're putting back in with the salts, but you're paying for the privilege of doing so!
 

JamesC

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gratts said:
That's limescale - just solidified minerals. Probably the same stuff you're putting back in with the salts, but you're paying for the privilege of doing so!
:lol: :lol: :lol:

That is so true. I actually found when I used RO water that the remineralising compounds weren't that good because they use sulphate salts which caused the TDS to go sky high. I had much better success cutting with tap water.

James
 

JazzyJeff

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If you have an RO unit that has the membrane over the top of 2 or 3 pods then all you need do is cut the pipe as it leaves the pods before entering the membranes and insert a T-peice and a Tap all available online for about £4 and when you want clean tapwater with all nasties taken out you can turn on the tap and run this water off, then add as much back too your RO water till you have the right Hardness/PH etc then there is no need for remineralising additives !!!!!!! been doing it this way for my discus for many years !!!!!!
 

Themuleous

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chris1004 said:
Themuleous said:
Yeh I would. Also why not mix the RO with tap to get the desired hardness? Save you a fortune in re-mineralisation salts :)

Sam
I wouldn't, I mean whats the point? you've just filtered the water to get all the nasties out of it then you go and put some back in!!! As for saving a fortune on remineralising salts that simply isn't true. A 250gram denerele remineral+ for examole is about a tenner and will treat 5000 litres (to kh1 I presume) therefore it is around 0.2p per litrekh or 40p to raise 200litres by 1kh (hardly a fortune in this hobby). If you use the AE gh plus it works out even cheaper. At least with remineraling salts you know whats gone back into the water. A lot depends on your tapwater to start with, how much you want to raise the kh by and how paranoid you are about water quality I suppose.
What do you mean by 'nasties'?

Also, lets take a 60lt tank, a reasonable size for most people. Using EI you need to change 30lt a week. Say you only raise it to 1dKH that's 6p a week on re-mineralisation salts. So £3.20 a year. And that's assuming its only 1dKH. Say you want to go to 5dKH, a reasonable level for most fish, that's 30p a week or £15.60 a year.

Now tap water (for me in the Thames Water region) costs around £1.50 for 1000 liters. My KH is 15d, so I only need to add 2lt to the 28lt to get the desired 1dKH. 1lt tap costs 0.15p so 0.3p a week or 15.6p a year. Now for 5dKH that's 10lt tap water or 3p a week or £1.56 a year. That's 10% the cost of using re-mineralisation salts. It also doesn't take into account the reduction in the amount of RO water you need to produce in the first place and as we all know the waste to product water radio for RO units is around 1:4. So if we use the 5dKH example, that's 20lt of RO you need a week, a saving of 10lt which is in fact 50lt due to the waste or 15p a week and £7.80 a year.

As you can see the costs rapidly mount up. And this is only on a 60lt tank.

chris1004 said:
I disagree, you should see the state that my kettle gets into......
How is limescale harmful? Hard water is actually good for you!

I'm always up for a good debate, but please be less aggressive in your posting.

Sam
 

chris1004

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gratts said:
That's limescale - just solidified minerals. Probably the same stuff you're putting back in with the salts, but you're paying for the privilege of doing so!
Yeah I know its just soloidified minerals but what minerals? Thats entirely the point. At least with remineralising salts you can be sure there is nothing there that could be harmfull.

You do it your way and I'll do it mine and good luck to you, I simply won't need any luck.......
 

chris1004

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Themuleous said:
I'm always up for a good debate, but please be less aggressive in your posting.

Sam

If you are offended by my post than I appologise but If you think I am being aggresive then you have led a very sheltered life my friend.........................



When considering 'nasties' I mean all things undesirable and as I am not a chemist I would find it impossible to pretend to know exactly what I am talking about there, that however doesn't matter a jot to me though. I mean by using 100% RO water and reminaralising nothing is left to chance. Luck, who needs it?

I also want to remove nitrates and phosphates and yes I know I will be putting them back in later by dosing my ferts which does on the face of it appear to be counter productive. However by starting with water with a oppm TDS and adding known quantities to the water I can be fairly confident of the parameters obtained within my tank and what they consist of, or at least the maximum quantities, and as I want to keep my nitrates as low as possible but still meet the needs of my plants I find this arrangement desirable, and as ferts are pretty cheap I don't worry about the money.

As for the cost calculations that you have worked out then fair enough it is easy to see how if your water is metered then the cost can go up quickly but mine isn't and I wouldn't care if it was. In the scheme of things in this hobby when you consider the ammount of money outlayed in a typical year is a further £20,£30,£40 or whatever really a huge saving? More to the point could it end up being a false economy?

I suppose things are also relative I mean if your budget is tight and £20 or so a year is a lot of money to you then fair enough, but to me I would gladly pay considerably more than that just for the peace of mind and not bat an eyelid especially when you consider the value of some of my fish (and I don't just mean monitary). So the cost of using 100% remineralised water plus the cost of adding ferts that have been previously removed add up over a year. What price do you put on peace of mind? As far as water quality goes I know that mine can't be any better 247 365 days a year and I wouldn't accept anything less.

As I said in my first reply on this topic a lot depends on the make-up of the water that you start with, what parameters you are trying to achieve and how paranoid you are about water quality.

Do I think its absolutly necessary? NO.
Do I think that is the way to go for all species of fish? NO.
 

Ed Seeley

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I also remineralise my RO water with remineralising salts. I use a mixture of RO Right and Equilibrium.

Why do I use (and have to buy) them instead of adding a small amount of tap water?

Well I keep all my tanks at 3-4dGH and 0dKH and want this low hardness for the fish I keep. I also don't dose heavily and want to control what goes into my tank water and not add lots of extra nitrate and phosphate that may come in via my tap water (This is because I'm lazy and when I dose I simply add a 25ml amount of macro and micro solutions which are gauged to give the correct proportions of all the ferts so I don't have to think about it! BTW I use the dosing bottles from AE where you squeeze the bottle and fill the top section then dump it in, like those used for medication which are great). In fact some of my unplanted tanks don't even have any GH added but run have water changes with straight RO (there is still some minerals in there due to the filtration and the fish get all the minerals they need from their food).

I also find it much more convenient to simply add a teaspoon of the RO salts rather than get the right amount of tap water in the container when filling it!
 

gratts

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and the fish get all the minerals they need from their food)
I thought the minerals in the water were more involved with keeping an osmotic balance between the fish and water rather than the fish ingesting them?
What fish do you keep Ed? Plenty from SA I hope? :D
 

Ed Seeley

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gratts said:
and the fish get all the minerals they need from their food)
I thought the minerals in the water were more involved with keeping an osmotic balance between the fish and water rather than the fish ingesting them?
What fish do you keep Ed? Plenty from SA I hope? :D
There may be an issue with osmotic balance for certain species but soft water fish are adapted to deal with very low levels. TDS tests in wild locations can be almost unmeasurable and even koi mud ponds in Japan have levels as low as 30ppm. My tanks run higher than that with straight RO water changes. I've heard some people say that pure RO means growing fish will be stunted due to lack of minerals. In fact some discus breeders say their young grow better in hard water. I've not read any scientific papers that have explored the links but I know that many koi keepers soften their water as it makes koi grow quicker! Nobody really seems to understand why though!

I've got killifish (mainly West African species but 1 type of Nothobranchius) and have kept a range of South and West African Dwarf cichlids over the years. At the moment I've only got a few; a lone male Apistogramma eremnopyge, 4 A.agassizii 'Double Red' (Spawning regularly but not successfully raising young yet), 1 male Pelvicachromis pulcher 'Super Red' (soon to be crossed with an albino female to try and get a Super Red albino strain - kribs are not usual albinos and do have some pigmentation in the heterozygous form so this might be possible), Pelvicachromis suboccellatus 'Matadi' and Steatocranus tinanti. I've also got a pair of wild Pterrophyllum scalare 'Peru Altum' that I'm spoiling rotten to try and get to breed at the expense of the scape in that tank!
 

Themuleous

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chris1004 said:
If you are offended by my post than I appologise but If you think I am being aggresive then you have led a very sheltered life my friend.........................
No offence taken so no apology needed :) but remember that there are ways and ways of saying something.

There are also ways and ways of achieving the same result. If you feel that you have to use 100% RO then I am not disagreeing with that approach, but I would disagree that it is the only approach, which is the impression I got form your posts. I was merely pointing out that its not! :lol:

Sam
 

chris1004

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Themuleous said:
chris1004 said:
If you are offended by my post than I appologise but If you think I am being aggresive then you have led a very sheltered life my friend.........................
No offence taken so no apology needed :) but remember that there are ways and ways of saying something.
Sam
Well obviously it bothered you or you wouldn't have said "there are ways and ways of saying somthing".

Whats the matter can't you handle someone disagreeing with you? Because that is all I did, in actual fact it wasn't even in response to your post that I used the words "I disagree" whilst refering to the gunk in my kettle. The actual words that I used when replying to your post was "I wouldn't" and then I gave a brief outline of why and set the record straight about what I believe to be the misleading cost implications detailed in your post.

As far as I am concerned I haven't done or said anything wrong, ridiculed anyone, been rude, ignorant or arogant nor have i disrespected anyone, but I did apologise just in case, now you see fit to 'teach' me the error of my ways........ :twisted: :twisted:
 

Themuleous

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I think we are going to have to agree to disagree, my friend. Probably not even that, its just a misunderstanding. I have taken no offence and am not 'bothered' by what you said :)

Sam
 
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