Ph Controllers

[Cameronb_01]

Hi Guys,
 
I have been keeping tropical fish now for three years and I have  always wanted to keep discus fish. However they require quite low Ph and for years I have been told by the people in my LFS that the only way to do this is by using a barrel to collect rainwater or by putting a large expensive contraption under my kitchen sink. However one day I went into my LFS to pick up some food and I see at the counter a "Ph Controller". This apparently just changes the Ph to whatever you want it, surely it is too good to be true?
I have the following questions about it:
 
1. Do they actually work and if so how do they do so.
2. What kind of price am I looking at?
3. What is the maintenance like?
4. If I want to keep fish in a lower Ph than my tap water is this the easiest and lowest maintenance way to do it?
 
Thanks so much in advance for all your replies.
 
Cameron
 
Also are there any imp-articular that you would recommend for a 450L tank?

 

[SherLar]

   Never heard of a PH controller. It does sound too good to be true. If there is an aquarium club in your area, maybe someone there knows about it.
   3 of the 4 LFSs in my area sell RO water for about .50 per gallon, which normally has a PH of 7.0, but it would make for expensive water changes if you had to buy water every time. 
   Well-rinsed peat placed in a media bag inside your filter should help to lower PH, but if your water is very hard, it's difficult to keep PH low. My wife would love to have a discus tank also, but our well water is much too hard and base for them. If there were such a thing as a viable PH controller, it would be worth the expense.

 

[Byron]

If there was a device that actually changed and maintained a pH different from the source water I am certain we would all have known about it.  I searched one of these and can understand the monitoring, but the "controlling" was not explained and I suspect it means something other than what one might think it does.  Perhaps a member with experience can provide more data.  I'll move on to your question 4 which I can answer.
 
The pH is one aspect of water chemistry that also includes the GH (general hardness) and KH (carbonate hardness, also called Alkalinity).  Generally, the harder the water, the higher the pH, and conversely; I say generally, because one might have higher pH with lower (soft to very soft) water.
 
Water in its pure form does not exist in nature; it is a powerful solvent, meaning a substance that easily dissolves other substances to create a solution. As rain falls, it picks up many gasses and particulate matter, and it continues to do this as it passes through the ground. Natural water values therefore vary with respect to hardness and pH because the water acquires specific properties from the landscape. Water flowing over or through rock will assimilate minerals from the rock, becoming what we term “hard” water. Water flowing through soils that contain organic matter will be “soft” because the organics bind with and thus remove minerals while creating acids that enter the water. The pH is largely the result of the hardness as well as the amount of carbon dioxide dissolved in the water.
 
The first thing to know is the GH and KH of your source water.  If you have a reliable liquid test kit for GH and KH, fine, but if not, don't rush out to buy one.  You should be able to obtain these numbers from the water authority if you are on municipal water; check for their website, or call them.  Once we know the GH and KH values, and the pH out of the tap, we will have a better idea of what may be involved.  BTW, when testing tap water for pH, let a glass of water stand for 24 hours to out-gas the CO2; otherwise, depending upon the amount of dissolved CO2, the pH test may be inaccurate.
 
There are a couple of methods, depending upon the numbers for the GH, KH and pH, so I won't go further into this until we know what we are dealing with.

 

[Cameronb_01]

Thanks so much for your responses. The products in my LFS were these: 
I believe it operates using CO2 or something? What do you think?
Link1: http/www.swelluk.com/jbl-proflora-ph-control/?gclid=CNGDqL66-MoCFbEy0wodI3UC-Q
Link2:http/www.co2supermarket.co.uk/precision-co2-ph-controller-for-planted-tanks-up-p208.html
And what I found:
Link3:http/greenleafaquariums.com/products/gla-gro-co2-system-advanced.html

 

[Byron]

You're in a very different area with those links.  None of them "change" the pH, directly, they just monitor it and tell you what it is and where it should be for what you set it.
 
The third is a CO2 regulator, and this is used by high-tech planted tank aquarists to grow lush plants.  This will lower pH, depending, but you are still bound by the GH and KH.
 
You haven't given us the GH and KH so we are still in the dark.

 
Byron.

 

[Cameronb_01]

GH=7
KH=5
 
Also for the unit this is the most up to date link, (the one the people in my LFS recommended): http/www.aquaristikshop.com/aquaristic/JBL-ProFlora-m503-CO2-Complete-System/128812/?gl=GB&gclid=CKHli9Gr-soCFSsz0wodncQE1w

 

[Byron]

GH=7
KH=5
 
Also for the unit this is the most up to date link, (the one the people in my LFS recommended): http/www.aquaristikshop.com/aquaristic/JBL-ProFlora-m503-CO2-Complete-System/128812/?gl=GB&gclid=CKHli9Gr-soCFSsz0wodncQE1w

 
What unit is being used for those numbers?  "Unit" means ppm (parts per million), mg/l (milligrams per litre), dGH (degrees), or maybe Clark (which is common in the UK).  These are different.
 
Also, I just went back in this thread and note that the actual pH of your tap water is not indicated.  This we need to know.  If you test tap water for pH, remember to out-gas the CO2 first, or the reading may be much lower than the true pH.

 

[Cameronb_01]

Sorry the unit was dGH

 

[HarpyFishLover]

Wow, I might try one to see if it works

 

[StevenF]

All the links Camernob are either PH meter or CO2 systems. None will let you enter a PH number you want and then magically set the water to that PH. A meter just measure the PH it doesn't do anything else. it cannot move the PH up or down.  CO2 systems just inject CO2 into the tank with the goal of improving plant growth.  Adding CO2 to water will lower PH but with a KH of 5 the effect will be minimal.  
 
The only way Camernob can lower his PH to more accurately match the natural envirnment of a particular fish is to switch from Tap water to distilled or RO water.