Reverse osmosis water, low ph, tank lost good bacteria?

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SandyCheeks

Aquarium Advice Freak
Joined
Feb 6, 2013
Messages
216
Location
Rural Nevada, USA
Set up a 5 gal tank for apple snail and 2 ghost shrimp. It was cycled. Ph 7.6, Ammonia stayed at 0, nitrites 0, nitrates 20-40. But then I noticed the ph dropped to 6. I thought this wasnt great but nothing too big. Then Ammonia went up to 1.0 and no Nitrite reading. I was using reverse osmosis water for weekly changes. Would this cause a low ph? And then cause an ammonia spike?
 
I think you need to add minerals back to r/o water to keep your pH stable. Yes a pH of 6 will shut down your bb.
 
If you're using RO or RO/DI, you've got to add a buffer before doing a water change.

FWIW, a pH of 6 will mean that ammonia is far less toxic (if it's even toxic at all) than if it were higher.
 
If you're using RO or RO/DI, you've got to add a buffer before doing a water change.

FWIW, a pH of 6 will mean that ammonia is far less toxic (if it's even toxic at all) than if it were higher.

Thanks everyone for the info!

What does it mean to buffer the water?

We have 3 water sources in our home:
R/O ((drinking) Ph 7.0
inside tap from a water softener. Ph 7.6
outside tap from the city. Ph 8.0.

I wonder why the Ph dropped like that. Weird.

Would it balance the Ph if I used 1/2 outside tap and 1/2 R/O? I have to heat half the water anyway.
 
Buffers are the minerals in water including calcium. When nitrates rise the water becomes more acidic, which eats up the calcium in the water and pH drops. Water changes with natural water that contains minerals, recharges things and maintains a stable pH. If you want to use your R/O water you can get mineral additives to restore the minerals. Fish need minerals to be healthy too.
 
[QUOTE="SandyCheeks;]

Would it balance the Ph if I used 1/2 outside tap and 1/2 R/O? I have to heat half the water anyway.[/QUOTE]

It would help. You will have to monitor the pH to see if it helps enough.
 
I can pretty much guarantee that if you mix RO water with tap water, you will end up with the same ph as the tap water. This is due to the tap water being hard (high KH) and thus very stable. If you mix the 2 you need to test ph before adding it to your tank otherwise you could seriously stress your fish
 
The pH of your normal, non R/O water should be fine if you want to use it. Just switch over slowly by doing several small water changes. But you can continue to use R/O if you add buffering chemicals.
 
Thanks guys for the advice. This can be confusing and you all help a lot. I was really amazed as to how much is involved, even a small tank.

Since I'm not too sure yet what I'm doing and don't want to stress the critters, I think for now it would be better for me to keep using the RO water for this tank. I assumed that RO water was better cuz it removes minerals, not knowing that fish need minerals just like we do. Makes sense cuz wild fish live in lakes and ponds full of minerals. I'll go online and buy some buffers. Once the tank is cycled again I'll do small water changes, slowly switching to regular city water and keeping a close eye on the Ph.
 
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