When To Add Mopani Wood?

[Lazerus]

Hi there,

Just a question on Mopani wood….

I have a very small piece about the size of my hand currently cooling in a pot of boiled water…I’ve boiled it and thrown the water off three times and the water was running clear enough now.

I don’t mind a bit of colour in my water though so its not that critical if its not fully clear.

The reason I’m adding the Mopani wood is to bring down my PH…which is a 7.8…and Cardinal tetras like a much lower PH. (I've a 10 gal tank by the way)

Is it safe to add this wood into the tank tomorrow morning when it’s cool?

(My tank is still possibly cycling, although it looks like it could be cycled by now, as I’ve had 0 Ammonia & 0 Nitrite for a while now….the vote is out on this though, as I mysteriously have 0 Nitrate also. But that topic is in another post!)

There won’t be any drastic drop to the PH will there? I believe the Mopani wood will drop the PH very slowly...is this true?

Or should I hold off for any reason? Is there any pitfall to adding this wood to my tank, like, will it distress the fish too much seeing as it wasn't in there from the beginning?

Thanks…

 

[backtotropical]

Hi Lazerus,

The only down-sides to Mopani Wood are that it can leach tannins into the water, turning it brown, and that it can lower the pH. These effects are not always desireable.

As you seem to be dealing with the tannins by boiling the wood, and the reason you are adding it is to lower the pH, i can see no problems at all. Do be aware that regardless of how much you boil it, it will probably still leach tannins, albeit not so much.

I see no reason to delay adding the wood. It will drop the pH slowly, so there is no problem there.

You should also be aware that Mopani wood may not lower the pH of the water at all, as it depends on the hardness of the water. If the water is very hard, the wood will have no effect on the pH. I urge you not to use powder buffers if this is the case as they will often make the situation worse. Most fish will tolerate a pH outside their recommended pH band with few problems, however no fish like a pH which swings around. This can be very harmful, and powder buffers can have that effect. A stable pH is far more important than a pH of the 'correct value'.

Hope that helps you, and good luck!

BTT

 

[ALW]

And if the wood dosent lower the pH, then you could put a peat sandwich in the filter, this could be done in addition to the wood.

 

[Lazerus]

Yes, that is a great help thanks!!!

And as I don’t know what powder buffers are yet, I can safely say I won’t be adding them to my tank…

But you have me curious now to find out what it is though so I’m off to look it up! Ho harm in knowing what NOT to do....fore warned is fore armed and all that.

Thanks again.

And if the wood dosent lower the pH, then you could put a peat sandwich in the filter, this could be done in addition to the wood.

I only have a Fluval 1 plus filter......In the event that the mopani wood doesn't work & I might have to use peat in the future to lower the ph, would I be able to fit in this peat sandwich in such a small filter?

 

[backtotropical]

But you have me curious now to find out what it is though so I’m off to look it up!

Basically, a pH buffer increases the kH (carbonate hardness) of the water. kH holds the pH stable so it doesn't swing around, so the higher the kH, the more resistant the water is to pH swings.

There is a good thread about it linked in my signature below, if you are interested to find out more.

 

[Lazerus]

Two more questions before I go ahead with the mopani wood….

Does it matter that I didn’t boil the wood in de-chlorinated water?


I had boiled the kettle first then put it into the pot and boiled away….but last night I left the wood sitting in a bucket of 50% cold water straight from the tap and 50% hot boiled water from the kettle…I never used any de-chlorinator in the bucket though. Hope this is not a major problem now.

I only thought about it at about 3am in the morning! Doh!

I’ve boiled the wood again this morning, and its now currently sitting in a bucket of de-chlorinated water. Perhaps it will be ok?

Also, about regular water changes…..

If my tank hopefully will now have a lower ph using this wood, then what will happen when I do my water changes…the PH will immediately rise again as the water out of my tap is 7.8.

Is this not going to shock the fish each time?

What do other people do to counter act this?

Many thanks!

 

[Lazerus]

I suppose what I'm trying to say is....if I'm doing my regular weekly 10% water change, will the Mopani wood effect my PH so much that I'll have to buy a PH lowering fluid to alter the new water in my bucket to match the current ph level in the tank?

(I've only a 10 gal tank with a small handsized piece of Mopani)

What I really need to know is with this amount of wood, I have to worry about flucutating PH levels from week to week after I do my water changes? I just don't want to go down that road.

 

[ALW]

To answer the first question on boiling the wood in De-chlorinated water. No you dont after boil the wood in De-chor. The wood will slowly lower the pH of the tank water, it may take a week for it to lower the pH (depends on the size of the wood and how much tannins left inside). After a water change the pH may then rise a little but then will fall again. It shouldnt fall that much that quickly to cause any stress on the fish.

 

[Miss Wiggle]

tbh mopani affects pH least of all the sorts of wood you can get, it's practically inert so i wouldn't worry over it.

i would suggest having a read of the link in my sig 'pH and KH' which talks about sensible ways to adjust pH

 

[Aussie_Dog]

All I know about Mopani is that it's one of the best woods (fish seem to like it best), but one of the worst tannin-leakers. I read one person's review who said that even if you boil for a week straight, it can take up to 6 months for the wood to stop leaking tannins (she still boasted about it's quality, though)

I have a piece in my tank and even though I boiled for a week, it still leaks. It's nothing bad, just the slightest tea color. I'll give it time and eventually the water will be clear again. I don't really care about the color of the water as long as the plecos are sucking on it all day long, lol

 

[ALW]

Some fish prefer to have tanins in the water anyway

 

[Lazerus]

Hi again…Thanks for the replies.

Well, I put the piece into the tank yesterday and the fish loved it! They were flocking around it all day. There must be something in it that they like alright!

This morning there is a very, very minor tint to the water, but I think it looks great! It gives a real sense of depth to the tank.

So….I’ll watch the PH levels to see if anything happens, but from what I’m reading, I’m guessing its not going to drop much, if it even drops at all.

I may have to look into the peat sandwich thing instead.

Ok, Thanks so much!