Questions About Ph And Kh

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As a general rule, don't add anything to tap water to make it suit your fish. Get fish that will live in your tap water, otherwise you're opening up a whole can of trouble.

It's worth remembering, as drrobbyb pointed out, that tap water does have some stuff in it that leaves quite quickly, such as CO2, amongst other things, so you'll also find people using "aged" tap water, which is basically left in a loosely covered bucket for a day or so before using it.

It sounds like you have soft, acidic tap water, which is great for keeping amazonian fish such as cories, so in many ways you're lucky. Your oto's should be perfectly happy in this water as well. They'll probably care more about ammonia and such like than your pH issues. If you want hard water you'll struggle more as you'll need to treat your water to keep a stable tank. Snails tend to prefer harder water conditions, so you may struggle more, but I'm no expert as I'm not a great fan of the apple snails.

Overall, if I were you I'd make the most of what you've got, which is great water for keeping cories, apistos, angels, discus and such like. Many of the most popular aquarium fish. I have the reverse problem, with horribly hard tap water that is pretty much as high in organics and ammonia as they're allowed to have it, which does limit my options slightly with tap water.
 
thanks again Rob, it is starting to make sense a little bit - as I've said before the whole PH/GH/KH thing I find too difficult to get my head around but we can't all be good at everything I suppose. I understand what they mean but what they do to the tank/fish/snails is what I'm struggling with.

I had a chat with my Dad last night (he also keeps tropicals) and I said pretty much the same thing as you've just said. I don't want to start adding things to my water as I feel it could all go horribly wrong and I could start losing fish. I'm just going to have to keep fish that like my soft, acidic water. I still think my sand is buffering the water down from it's PH7 out of the tap to the PH6 that it ends up. The fry tank with different substrate and running at a constant PH7 is proof of that.

My Dad's tank is running at around PH 8 (he's going to check it again today) despite us having the same water source. It could be his substrate buffering aswell. We're going to get his KH checked and if it's better he's going to take my snail - and hope and pray his barbs don't see him as food :crazy:

As things stand the platies seem to have adjusted to the PH crash - there's no signs of them getting sick and they're just behaving no differently :)
 
If you keep your tank at a much lower ph than your tap water make sure to avoid large water changes as the sudden raise in ph could shock your fish. More frequent, smaller water changes are better.
 
If you keep your tank at a much lower ph than your tap water make sure to avoid large water changes as the sudden raise in ph could shock your fish. More frequent, smaller water changes are better.

Yeah, I was thinking about that. I'll keep the water changes to smaller ones rather than large
 
Akasha, My water has a really low KH, so I have to use crushed coral to avoid pH crashes. That is what I suspect is going on with your tank as well. You might want to invest in a KH test kit to verify all of this, and it will probably make all of this come into perspective for you. That's why I wanted you to read the link in my signature. It's a rare occurrence, however it does happen.

In my particular case, we live in an area that is nothing but granite mountains. Our water supply has next to zero calcium naturally occurring so this translates to a very low KH (carbonate hardness) and a wildly swinging pH. In my tanks I have to take steps to control this or my cycle will stall and my fish suffer for it (or I must change my water a lot more often that I wanted to.) But on the plus side, I have the perfect water for discus, angels, cories, or many other SA cichlids!
 
thanks drobbyb. I intend to get a KH test next week as you say it might all start making sense once I know what the KH is.

I've still got the small piece of coral rock in the tank. If it buffers it back up to the 7 mark it'll make water changes easier. It might take a while and I'm keeping an eye on things. What ever happens though I still think the snail is better off with someone else.

If I have little or no KH then his shell will start to suffer more the longer he stays in my tank.

If there's a mod reading this please can you tell me how I change the heading of this as I'm getting the help I need from other's.
Perhaps help with PH and KH may be a better heading. Thanks :)
 
thanks TTA, I'll have a read :)
 
The rock will certainly help some, but it needs flow over it to work properly. The more flow, the more effective it will be. But wait until you know your KH. If it's less than 4 (it takes less than 4 drops to change the color in the test tube if you get an API kit) then that explains everything you have been experiencing. That means you have such a low KH that your water doesn't have sufficient carbonate hardness to resist pH changes. As has been said before, this isn't a terrible thing! Some fish absolutely love this type of water, and discus, wild angel, and electric blue german ram breeders would kill for this naturally occurring water! The people who breed these fish usually change their water extremely frequently so they don't have to worry about a pH crash. But for most fish keepers, this isn't the norm. To go longer periods, we must buffer.

So, KH test kit it is! Gotta verify!
 
thanks again. I'll see if I can get a KH test on Tuesday. P@H have the API tests and my lfs has the tetra brand. I'd prefer API if I can get one (just cos that's what I'm used to) but if I can't I'll have to get the tetra one.

I've already checked Ebay and there none on there. I can always check again at the weekend
 
Done a water test on both tanks this morning.

Main tank = PH 6.2 (it's between 6 and 6.4 on the card) Ammonia 0, Nitrite 0

Fry tank (with old pebble substrate)= PH 7.2, Ammonia 0, Nitrite )


I am becoming very tempted to put the pebbles back in the main tank. Also the main tank has lost that musky smell that comes from a healthy cycled tank - this worries me a bit.

Is it anything to be concerned about? Am I losing bacteria now with this sand and the PH crash it's caused?
 
It sounds like those pebbles may have had some marble or limestone in them that had a bufferring effect on your water chemistry. You could take a hand full of those pebbles and put them in a small container of water for a few days and then check the pH. An airstone with airline and pump will speed the process. If it rises, this will verify that hypothesis.
 
I've just returned a 2 litre jug full of my old black pebbles back to the tank. I just can't cope with stressing about the PH crash anymore.

I'll start syphoning the sand underneath it bit by bit as simply removing it and putting back the pebbles in one day is too much to do and it could also cause a massive swing in PH and shock the fish.

Slowly does it for now. The coral is also out for now
 
PH is back up to 6.6 already and the fish ...? The cories are chasing around like nutters and the platies seem more active too
 
If the pH is already up, then there is definitely something buffering your water in the pebbles. Ok then, from this we can draw the conclusion that you do have a low KH (really soft water.) No more stressing! You can simply take a handfull of these pebbles and place them in a mesh bag inside your filter AND keep your sand! This will maintain your pH (just keep an eye on it and don't let it get too high so as to shock your fish when you do a waterchange)
 

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