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  Topic Review (Newest First)
11-28-2012 06:27 PM
uberape i can tell you how i lowered my 8ph tap water to 6-5.5 , if you like. the first thing to check is your substrate, some will buffer your ph and never let it go. get sand that will not alter or specific substrates that will not alter ph or better even lower it a little. you also have to mob the tank with driftwood, I have about 5 pieces in my 30g. I also filter with peat by putting sera peat balls in a pair of womens tights and putting it with the filter sponge (this is the least effective bit because i never change them, too expensive). I also use diy co2 which helps destabalise the water buffers allowing the bogwood etc to bring down the ph further, it also lowers the ph itself. last but not least 4-5 cattalpa leaves help a fair bit. Now two things to look out for, first buy an electric ph meter, you need to check a lot, so liquid testers are a waste of money. second you will need a ph down for water changes. you can alternatively use co2 tabs to bring the ph down in the bucket before adding. remember the ph meter is essential kit (10 e-bay) for this weekly process. but after you succeed, you can include all those lovely apistogramma species that would usually fail= well worth it. I warn you I am no expert but my method does not harm the fish because i keep fairly sensitive apisto's with no problems (they even breed in the tank). RO water i imagine is a good investment but only for a fish room not one tank.
11-28-2012 06:12 PM
Diana When the pH of the water is a concern the first questions ought to be:
What is the KH of the water?
Is the water company adding something to alter the pH?
Test the tap water:
GH, KH, TDS, pH right out of the tap, pH of some tap water that has sat out 24-48 hours.
Test the tank water:
GH, KH, TDS, pH.
__________________________________________________ _________

Carbonates are one of the most common buffers of pH in the water. If the KH is high then the pH will usually be high, and be difficult to alter. Adding the driftwood and seeing just a temporary result suggests the KH is high.

The proper way to alter the pH, when there are too many minerals in the water is to remove those minerals.

Fish are not actually looking for a particular pH, but the right mineral level. Almost always high pH is associated with high mineral levels that soft water fish do not like.
To keep or breed soft water fish, when your tap water is too hard, too high pH, do this:
Go buy a gallon of reverse osmosis water or distilled. From the aquarium point of view they are the same.
Test various blends of tap + RO.
25% tap + 75% RO
75% tap + 25% RO.
Test GH, KH, pH, TDS. Look first at the GH and TDS. Which is closest to what the fish want? (research the fish) Is the pH where you want it? You can now lower the pH by filtering that blend through peat moss. In this test you can add a handful of peat to a quart or a gallon of water and see where it gets you after 24 hours.
Whichever is close enough to what your fish want is what you will have to mix up each and every time. If you needed to use the peat moss, then that will have to be part of your water prep routine.
For initial set up and for water changes:
Run half a garbage can of RO, and top it off with tap water. Add dechlor.
Set up a pump to circulate the water.
Add peat moss. You could use a HOB or canister filter, if you have one, but I just put peat moss in a knee-hi stocking and use a fountain pump.
Add an aquarium heater.
Circulate the water for as long as needed until the peat moss has done its work. Overnight for sure, perhaps longer if you are reusing the peat moss. (I get several uses out of one stocking full of peat moss).

This can be a lot of work, and you might decide that keeping fish that are better suited to the tap water is a better idea.
Or you might find a system that works well for you and see this as not too much work to keep the fish that you like, but are not suited to your tap water.
11-28-2012 01:33 AM
specks Ok I will heed everyone's advice. I will not change anything.

Although the pH have been at 8+ from the start(two years ago), all the fish in my tank are perfectly fine. Even the neons are showing excellen coloration and very normal behavior.

Thank for all the help guys!
11-28-2012 01:26 AM
hobos Do yourself a favor and don't fight the water it will always win.
11-28-2012 01:24 AM
Originally Posted by fusiongt View Post
Some substrate like ADA Amazonia helps lower PH (as I believe there's some peat in there) and driftwood helps as well.

I think most (all?) of the substrates that tend to lower pH will get exhausted eventually.

what tomfromstlouis said may be the cheapest/quickest option.
11-28-2012 01:14 AM
tomfromstlouis This is a dangerous direction to go - it is nearly always best to adapt your fish to your water than your water to your fish - but it can be done. A Reverse Osmosis gizmo allows you to reconstitute water to your own specs or mix with tap to reduce pH.

If you decide you must lower your pH and do not want to go the RO route, here is what I did. First, I put lots of peat into a second canister filter. This managed to bring the tank down to 7.0. So far, so good. But not far enough, so I bought a gallon of muriatic acid from the paint section of a big box store. This is nasty toxic hydrochloric acid that eats through carpets if just one drop gets on it <ahem>, so wear safety glasses and gloves when handling it. By experimentation I learned that I needed 10 ml of acid (I used an old medicine dropper to measure) to lower 20 gallons of tap water from 7.6 to under 6.0. Do this in a separate container at least two days before mixing the aged water into your tank. The reason for this separate container and not just adding acid to the tank is this: the acid immediately drops the pH like a stone but as the buffers in your harder water chemically interact with the acid, pH rises back up. These pH shifts can kill fish. The right amount of acid "uses up" the buffers to just the right degree, so you must experiment to learn how much to use. It was not much in my case. Agitate the water as it ages. Use it for your next water change.
11-27-2012 10:24 PM
GeToChKn The main questions, is why do you want to lower it? If your fish/plants/shrimp are happy, messing with it and trying to balance it, is only going to create more problems that it solves.
11-27-2012 10:17 PM
fusiongt Some substrate like ADA Amazonia helps lower PH (as I believe there's some peat in there) and driftwood helps as well.

Do you already have fauna in your tank and are they doing okay? If they are doing fine, I wouldn't change it or I would change it very slowly. If you've yet to add in any fauna, then I suggest changing your substrate to one that helps lower the PH.
11-27-2012 10:15 PM
specks I do 10% weekly WC. Is there any other way to incorporate peat aside from pretreating water?
11-27-2012 08:51 PM
lochaber How often and how much of a water change do you do? And what is your current substrate?

Peat filtration can help. It might be worth setting up a tub with a small filter/airstone/circulation pump and using that to pretreat the water with peat, and then use that for water changes.
11-27-2012 01:49 PM
How to lower pH?

Hi folks,

My recent test shows that my pH is at 8.6! O_O And no, the test kit is not bad as it is only a year old and I did several test to confirm that it is still good.

Now, I'm looking for effective ways to lower this very high pH. Seven months ago, I added a fairly large piece of cured driftwood in my tank. It obviously stained the water and it did lower the pH to olny 8.2 for about a couple weeks and then it sprung back up.

Apparently, driftwood tannin does not work and my tank has a very good buffeting capacity though there are no sources of carbonates in the tank. Must be our local water. There are also visible buildups along the waterline.

What are some effective methods to lower the pH and hardness if possible except RO? Peat maybe but will it be enough? Please give me some suggestions.

I know that it's not really good to mess a stable pH but I want to try some softwater fish.


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