Hello, I just started a 65 gallon fish tank at Christmas and at first it seemed fine but then I noticed that I kept having algy blooms so I got a water test kit and it shows that my ph is around 8.6 which is nuts and every time I try get it down it goes right back up over night. my tap water is at about 7.4 so i'm not sure why this is happening. I had a bunch of dried coral and some shells whick i was told would make it go up so I took it out and have not noticed any difference. The fish seem fine but I have lost a few. So if anyone has any ideas I need all the help I can get.
Help I can't keep the ph down
- Thread starter liss
- Start date
Take some of your tap water and let it sit out overnight or for 12 hours. Test the pH. The number you get is your true pH out of the tap.
Please do not use chemicals to try to get your pH down. If your pH is truely that high, and it most likely is, your KH will be high as well and your pH will just bounce all over the place.
Do the test as outlined and post the result.
Roan
Please do not use chemicals to try to get your pH down. If your pH is truely that high, and it most likely is, your KH will be high as well and your pH will just bounce all over the place.
Do the test as outlined and post the result.
Roan
many municipal water systems contain alot of carbon dioxide. carbon dioxide is only water-soluble, when pressure is maintained .. as in the pipes which transfer water through your house. this CO2 is in equillibrium with carbonic acid ... which will lower your pH. when the water is discharged from the pipes, the pressure is released and the solubility of CO2 diminishes. the CO2 degasses to the atmosphere and the result is a higher pH as the system equillibrates to a 'normal' pH.
why? Carbon dioxide dissolves slightly in water to form a weak acid called carbonic acid, H2CO3, according to the following reaction: CO2 + H2O --> H2CO3. After that, carbonic acid reacts slightly and reversibly in water to form a hydronium cation, H3O+, and the bicarbonate ion, HCO3-, according to the following reaction: H2CO3 + H2O --> HCO3- + H3O+
the carbonate discussed above (measured as kH) acts as a 'buffer' which reacts with any 'acids' in your water to neutralize them. when you add chemicals, you're really adding acidic buffers (usually phosphate ... these cause major algae blooms) which cannot work to effectively lower your ph since they are 'used up' by the carbonate.
all that said .. there's nothing wrong with a pH of 8.6. many fish actually thrive in such conditions.
why? Carbon dioxide dissolves slightly in water to form a weak acid called carbonic acid, H2CO3, according to the following reaction: CO2 + H2O --> H2CO3. After that, carbonic acid reacts slightly and reversibly in water to form a hydronium cation, H3O+, and the bicarbonate ion, HCO3-, according to the following reaction: H2CO3 + H2O --> HCO3- + H3O+
the carbonate discussed above (measured as kH) acts as a 'buffer' which reacts with any 'acids' in your water to neutralize them. when you add chemicals, you're really adding acidic buffers (usually phosphate ... these cause major algae blooms) which cannot work to effectively lower your ph since they are 'used up' by the carbonate.
all that said .. there's nothing wrong with a pH of 8.6. many fish actually thrive in such conditions.
I agree with liv2padl. I had a similar question a few months back, as my water out of the tap was at 7.0, but in my tank it was 8.0. roans suggestion about sitting some tap water out overnight will illustrate how it happens, and gaining 1.0 in Ph overnight is a fairly common thing. essentially the CO2 in your water lines gasses off and it makes the Ph go up.
taking out the crushed coral and whatnot was probably a good thing, since you obviously don't need a higher Ph
if you are determined to bring it down, peat and driftwood will help, but if your Kh is high it may not do you much good as it will absorb any changes the driftwood and peat would make giving you no real changes anyway.
IME if you have a high Kh (which I do as well) you're better off leaving well enough alone, and do your best to provide a stable environment as opposed to trying to force your water into "optimal" conditions.
taking out the crushed coral and whatnot was probably a good thing, since you obviously don't need a higher Ph
if you are determined to bring it down, peat and driftwood will help, but if your Kh is high it may not do you much good as it will absorb any changes the driftwood and peat would make giving you no real changes anyway.IME if you have a high Kh (which I do as well) you're better off leaving well enough alone, and do your best to provide a stable environment as opposed to trying to force your water into "optimal" conditions.
What liv2padl and LunchBox stated is quite correct.
Also, before you even ask -- pH changes that are brought about by CO2 gasing off do not harm the fish at all. The CO2 doesn't actually "change" the water. It's chemicals added to the tank to "correct" the pH, and which actually change the water chemistry, that can harm the fish.
Roan
Also, before you even ask
-- pH changes that are brought about by CO2 gasing off do not harm the fish at all. The CO2 doesn't actually "change" the water. It's chemicals added to the tank to "correct" the pH, and which actually change the water chemistry, that can harm the fish.Roan
Wow, I did the tap water test last night and it was at about 7.6 and this moring was at about 8.2-8.4 I can't believe that. I couldn't find the kh test in town so I ordered one to see. What I also might try is buying water from the store and using that for my water changes to see if it will bring it down. Or do you think it will just go up again because my tank has been getting water with a higher PH? My fish do seem fine I have not lost any for a while but now my tank is going through another algae bloom I have had at least 5 since Feb and I have been using the algae destroyer which works great but then almost always my plecostomus dies so this time I am trying to only use half the dose to see if that will help. Any ideas to getting it to go away on its own?
Stop using the algae killer stuff right away! It can kill your fish...
If your grocery store sells water you can fill your own jugs with, check the machine which dispenses it for "Water filtered by reverse osmosis" This water has no hardness and a neutral pH. If you mix it with your tap water, yes, your water will get 'softer' and your pH will go down. This is actually the best means to lower your pH. Come up with your desired water 'recipe', in my case I use 4g RO water for every 1g tap, then I add back in some electrolytes (Kent's RO Right), etc. Then with every water change, use your new 'recipe'. Bit by bit your pH will gradually lower and this is sooo much easier on the fish! It will take some time, but if your fish are accimated to your water now, you really want to go slow to change it.
Find out what your kH is before you make anymore changes though. Algae blooms won't kill your fish, just be patient until we can get your water readings and then come up with the safest/fastest solution.
Cathy
If your grocery store sells water you can fill your own jugs with, check the machine which dispenses it for "Water filtered by reverse osmosis" This water has no hardness and a neutral pH. If you mix it with your tap water, yes, your water will get 'softer' and your pH will go down. This is actually the best means to lower your pH. Come up with your desired water 'recipe', in my case I use 4g RO water for every 1g tap, then I add back in some electrolytes (Kent's RO Right), etc. Then with every water change, use your new 'recipe'. Bit by bit your pH will gradually lower and this is sooo much easier on the fish! It will take some time, but if your fish are accimated to your water now, you really want to go slow to change it.
Find out what your kH is before you make anymore changes though. Algae blooms won't kill your fish, just be patient until we can get your water readings and then come up with the safest/fastest solution.
Cathy
Hi Cathy thanks for all the info on the store water. I will be trying that as soon as I do another water change. I should have the KH tester in in the next few days I hope. I will post what the results are as soon as I know. I do have a water softener in my house but I don't have RO do you think if I turned it up to make the water softer that that would help?
it's more complicated than that. when you run water through a home water softener, the anions Ca++ and Mg++ are exchanged for sodium (Na+) but notice the difference in electron charge ... Calcium is a divalent anion (++) but sodium is monovalent (+). this means that when the calcium is exchanged, TWO sodiums must replace ONE calcium or magnesium. the net effect is that while you are softening your water with respect to your laundry and those white spots on your faucet, you are actually INCREASING the total dissolved solids of your water. fish don't do laundry and thus they are more affected by the TDS of your water than they are with which particular anion it contains.
frankly, i think you're making alot more out of this than is necessary. your fish will likely be just fine in the water you've got, wi;thout you messing with it. wouldn't that be alot easier?