undergroundfish Posted July 11, 2011 Report Share Posted July 11, 2011 Hi, we have quite hard water 7.5 + How do I get a sustainable P.h of between 5.5 to 7.2 Quote Link to comment Share on other sites More sharing options...
ryanjury Posted July 11, 2011 Report Share Posted July 11, 2011 What is the KH of your water? Quote Link to comment Share on other sites More sharing options...
David R Posted July 11, 2011 Report Share Posted July 11, 2011 Hard or basic? GH and KH are more important that pH, if your water is coming out of the tap at 7.5 and you want it lower than that then you really need to know the hardness. If the hardness is low it may be as simple as adding a bit of driftwood and/or peat to your tank, but if the water has a high mineral content (if you're getting it from a spring/bore in a limestone area, for example) you may need to look at collecting rainwater or a Reverse Osmosis unit. Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted July 11, 2011 Report Share Posted July 11, 2011 Ph has nothing to do with hardness which is caused by calcium and magnesium ions. Quote Link to comment Share on other sites More sharing options...
David R Posted July 12, 2011 Report Share Posted July 12, 2011 Perhaps you could explain it for all of us then and answer the OP's question. I'm no chemist, but I always thought that high hardness made it difficult to lower pH (ie the water has more "buffer") but I guess not if they have nothing to do with each other.. Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted July 12, 2011 Report Share Posted July 12, 2011 pH (small p and Capital H) is minus the log of the hydrogen ion concentration. Put into english that is that 7 is neutral and if you add an acid to neutral water at 7 and one drop takes the pH from 7 to 6 then it will take 10 drops to take it to 5 and 100 drops to take it to 4. An acid is a solution that provides hydrogen ions (hydrogen atoms with an electron missing). Conversally if you add an alkali (a solution that provides hydroxyl ions) to a neutral solution and one drop moves it from 7 to 8 then it will take 10 drops to move it from 8 to 9. Hardness is a measure of the amount of Calcium and magnesium ions in the water. The term hardness relates to the hardness of getting soap to lather in the water and the original measure of hardness was a titration of a known solution of soap and when the water was able to froth the hardness had been used up and the soap woul start to work. Soap is made by boiling caustic soda (sodium hydroxide) with fat and this makes soap (sodiun stearate) and glycerine. The sodium in the soap swaps over with the calcium and forms calcium stearate which is insoluble and becomes the scum on your bath. If you add calcium carbonate (mable chips, chalk etc) it reacts with the hydrogen ions and removes them from the water which becomes less acid. It is not the calcium that does that but the carbonate or bicarboate (which is more soluble than carbonate). There endith the lesson for today. Quote Link to comment Share on other sites More sharing options...
David R Posted July 12, 2011 Report Share Posted July 12, 2011 and so in conclusion to answer the original question of "how do I make my pH 7.5+ water into stable pH 5.5 water?: ........... Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted July 12, 2011 Report Share Posted July 12, 2011 You don't. If you play with it you will be forever chasing it. The only way I know of is to add things like peat that will make it acid but unlikely to get to 5.5 I would have thought. You have to add hydrogen ions to lower the pH and hydroxyl ions to raise it above 7. Quote Link to comment Share on other sites More sharing options...
GZ_Loach Posted July 12, 2011 Report Share Posted July 12, 2011 collect rain water or add bogwood/peat to the tank. 7.5 is pretty normal, city water is made to be between 7 and 7.5 so that pipes don't corrode. Quote Link to comment Share on other sites More sharing options...
ryanjury Posted July 12, 2011 Report Share Posted July 12, 2011 If the KH is low then the PH will drop with the addition of peat etc, you can add some driftwood/peat and then a little bit of crushed coral etc to keep it stable.. What is your intention with trying to lower the PH? Quote Link to comment Share on other sites More sharing options...
undergroundfish Posted July 12, 2011 Author Report Share Posted July 12, 2011 Ok, I have a ph of well over 7.5 (my ph test kit doesn't go beyond 7.5) but I want a ph of 5.5 to 7.2 because the fish I intend to get require it. Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted July 12, 2011 Report Share Posted July 12, 2011 To make the water more acid you need to add hydrogen ions in the form of: Carbonic acid from injecting CO2, tannic acid from adding driftwood or oak leaves or tea bags, or rainwater which is usually contaminated with sulphur dioxide. It will not take a lot to change it to 7.2 but 5.5 is a bit more of an ask. If I remember correctly Coca Cola is about 4.6 and that contains a lot of carbonic acid which is carbon dioxide in solution. Quote Link to comment Share on other sites More sharing options...
undergroundfish Posted July 12, 2011 Author Report Share Posted July 12, 2011 Thanks for that. So can someone clarify for me what putting crushed oyster shells in will do to the water in a tank? Quote Link to comment Share on other sites More sharing options...
Ira Posted July 12, 2011 Report Share Posted July 12, 2011 To make the water more acid you need to add hydrogen ions in the form of: Carbonic acid from injecting CO2, tannic acid from adding driftwood or oak leaves or tea bags, or rainwater which is usually contaminated with sulphur dioxide. It will not take a lot to change it to 7.2 but 5.5 is a bit more of an ask. If I remember correctly Coca Cola is about 4.6 and that contains a lot of carbonic acid which is carbon dioxide in solution. And phosphoric acid. Thanks for that. So can someone clarify for me what putting crushed oyster shells in will do to the water in a tank? Increase the ph and make the water harder. Quote Link to comment Share on other sites More sharing options...
jim r Posted July 12, 2011 Report Share Posted July 12, 2011 When I was breeding my discus way back in the early 80's I used hydrochloric acid and I got the info from Jack Wattley's handbook of Discus. Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted July 12, 2011 Report Share Posted July 12, 2011 I have used hydrochloric because phosphoric is milder but can cause algae problems. I don't us chemicals now, just get fish used to what I have got. Fish will tolerate a reasonable range of pH if it changes slowly. It is more important with some fish if you are trying to breed them. Quote Link to comment Share on other sites More sharing options...
undergroundfish Posted July 19, 2011 Author Report Share Posted July 19, 2011 So in the end I didnt listen to anyone and used my pH kit to correct the pH. When I got home from work the pH was out of wack again :an!gry What I did do was buy a kH kit and test the hardness. As suspected my water is very hard and the water the fish came in is soft. The peat managed to bring this down a bit. The fish had to go in or die in plastic bags so I took the risk. For now they seem to be ok I used stress coat, and stress zhyme also I admit I was a little unprepared for the arrival. and the tank is only a temporary measure while I sort there proper one Quote Link to comment Share on other sites More sharing options...
the-obstacle Posted July 19, 2011 Report Share Posted July 19, 2011 If you acclimated the fish slowly enough they won't mind the change. Sounds like they're doing well though so all good. Quote Link to comment Share on other sites More sharing options...
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