Do I Need To Take Action?

[CezzaXV]

I've got some wood, I believe it's redmoor. It stopped leeching tannins months ago though, and even if it hadn't I was told that the effect of tannins on pH isn't as much as people would have you believe.

 

[snazy]

I have wood in all my tanks and the Ph of my tap water is 6.6 and tanks with wood are 7.6 so the wood is not reducing anything really in my case.

 

[KittyKat]

will abit of tuffa rock raise ph ?

Does it fail the vinegar test? If yes, then probably yes.

I've got some wood, I believe it's redmoor. It stopped leeching tannins months ago though, and even if it hadn't I was told that the effect of tannins on pH isn't as much as people would have you believe.

In my experience, it's as much as people would have you believe… a few years ago, I lined the back of the tank with wood and that dropped the pH from around 8.0 to 5.0 (it was stable before the wood was added and was stable after, no fish were in the tank at the time).

I do recommend that you either add some reef bones and/or shells to your decor, or add some crushed coral/shells to your filter. If you do this, do keep in mind that you will be limited to smaller water changes only and you should start with smaller quantities, increasing as needed. KH is carbonates, so you are only trying to increase carbonate content of the water, but at a sustainable rate (the things I mention all leach into water at a constant rate, so even if the acid is using them up, they should be able to maintain the "supply", unlike liquid and solid buffers that are "one off" additions, which is why they are risky). Ideally, you should get your KH to around 5-6 degrees before it can be considered stable

 

[Proxo]

I've got some wood, I believe it's redmoor. It stopped leeching tannins months ago though, and even if it hadn't I was told that the effect of tannins on pH isn't as much as people would have you believe.

I got a pH drop to 6.2 from 7.6 with a few small chunks of wood over roughly 2weeks, stabled back out with water changes @ roughly 6.8-7.0 though!
Saying that though on another tank it dropped next to nothing lol.

 

[CezzaXV]

Well, I don't consider removing the wood an option, but I'm hoping to be able to get hold of some crushed coral to add to my filter in addition to the small shells I have inside my filter and larger ones I have as part of my decor.

How much should I be looking to add? I'm running a Fluval 205, so would half a basket be enough or too much?

 

[KittyKat]

I'd start with a small handful, and probably wouldn't go above one basket.

 

[CezzaXV]

Okay, thanks.

I've heard about KH shock for fish but can't really find much info on it. I have previously done big water changes twice a week, but obviously my tap water has a low KH. How much of a change in KH can my fish comfortably handle?

 

[snazy]

You can measure the Ph instead. As far as I know a change more than 0.3 will cause stress. This is not 3 points though. So a Ph change from 6.5 to 6.8 for example is something the fish will tolerate but not more. So you need to do it slowly.

 

[CezzaXV]

Okay, not a problem. The pH tends to fluctuate wildly in my tank (as I previously said my tank went from 6.0 to 6.8 in 24 hours and this isn't even unusual) but the fish are all somehow still alive. I refill using a hose straight from the tap, so dripping it in over the space of hours isn't a problem, even if I have to hose it into a bucket and dechlor it first rather than dose straight into the tank and have to have the filter off for that long.

 

[Primous]

A swing of 0.8 is nothing for you to worry about. To clarify my initial post I was talking about a swing of 5.0 in either direction not 0.5. You are well within the margin and there is no need to buy anything even though you seem determined to. I am on another forum which has more US members and there ph is a roller coaster in comparison to Europe there they can get +4 in either direction and the fish adjust and remain unaffected.

Snazy hit the nail on the head with her initial post also. Nitrates can affect your ph and since they are already a concern I'd suggest you make an effort to lower them before buying anything. And by the way Nitrates @30ppm+ in a week is way to high

 

[CezzaXV]

My nitrates haven't risen 30ppm in a week, they've risen to 30ppm since my last water change which was on thursday. My tap water has 10-20ppm of nitrate whenever I test it so I've only had at most a 20ppm rise (and in reality, likely less than that). I was under the impression that 30ppm was a perfectly acceptable level, and my water change schedule is frequent enough that I'm removing them quicker than they're building up.

 

[snazy]

I can't tell at want point nitrAtes affect the Ph but they do. There are many examples here on the forum when Ph crashed in tanks during fishless cycling when obviously there is a lot of ammonia to nitrIte conversion and a lot of nitrAtes that may contribute to nitric acid and similar stuff.
The process of converting ammonia to nitrites releases free hydrogen ions that naturally make the water acidic too.

If your tap water has 20ppm nitrAtes and in 3 days from Thursday you have 40ppm nitrAtes in your tank water, then maybe it's a bit on the high side if you have plants in the tank too. I've personally had 40ppm nitrAtes no bother in a week time but again my tap water has no Kh issues either so I deal with one problem only.

Edit: And again, I can't tell the difference between 20ppm and 40ppm on my Api nitrAte test, not to mind 30ppm. That's why I try to keep it in the orange range

 

[Primous]

I too have no idea at what point nitrates will crash your ph, only that it can at certain levels. But since your tap water is already high in nitrates don't worry or pay much attention to it or you'll/we'll risk getting side-tracked. The fact remains that a swing of less than 5.0 is nothing to worry about. at 0.8 = you're in extremely good territory.

As you can see, it fluctuates quite a bit! I really have no idea how my fish are still alive!

They're alive because they've adjusted to their environment and a ph swing of 0.8 is neither here nor there to them.

 

[CezzaXV]

Just done another nitrate test, it's looking much the same as yesterday. Too orange for 20ppm but not red enough for 40ppm. Maybe a little closer to the red side today than it was yesterday though. pH is 7.4, a 0.6 increase from yesterday. It's looking unlikely that nitrates are the problem, given the fact that my nitrates have gone up since I had that 6.0 two days ago, and now my pH is 7.4. This actually makes it ideal for my water change tomorrow as my tap water pH is 7.2 so less of a change, but that's beside the point.

It'd be nice to be able to keep my nitrates in the orange range, but coming out of the tap they're already close to the upper limits. I have been testing my water much more recently as it's interesting me. Will test before my water change tomorrow, make a record of how much water I change and measure the nitrate after, and keep a record of it each day until my next water change. I know this is slightly off topic to my pH/KH issue now, but it's got me interested.