# Mopani wood oozing sap, now what?



## DKRST (Jan 11, 2011)

How do I thoroughly cure a piece of mopani wood? 
I got a great "deal" on a beautiful piece and have been soaking it for three days to leach out the tannins. I noticed today there is (very) sticky sap oozing out of the wood! Obviously it was not cured properly. The piece is great, but it's not going into a tank until I know it's safe. I can steam-sterilize it repeatedly at work, no problem. My question is, will this drive out the sap or should I just let the piece bake in the sun for a year or so? Can it be cured in a regular oven on low heat?


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## GwenInNM (Feb 2, 2011)

DKRST said:


> How do I thoroughly cure a piece of mopani wood?
> I got a great "deal" on a beautiful piece and have been soaking it for three days to leach out the tannins. I noticed today there is (very) sticky sap oozing out of the wood! Obviously it was not cured properly. The piece is great, but it's not going into a tank until I know it's safe. I can steam-sterilize it repeatedly at work, no problem. My question is, will this drive out the sap or should I just let the piece bake in the sun for a year or so? Can it be cured in a regular oven on low heat?



I bet others will tell you not to chance it by putting it in your tank. I think sap can be a problem. I boiled my mopani wood for hours, dumping the brown liquid and refreshing water. That did work to get the tannin out, but I have no clue about the sap.

Gwen


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## redchigh (Jan 20, 2010)

I would bake it at 350 degrees for 2 weeks.


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## Boredomb (Feb 21, 2011)

redchigh said:


> I would bake it at 350 degrees for 2 weeks.



WoW! that would be one high energy bill!!! LoL


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## redchigh (Jan 20, 2010)

Normally Mopani bakes out in the sun for decades, centuries even.


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## DKRST (Jan 11, 2011)

*Update*

I took the mopani piece to work and autoclaved it (pressure steam-sterilized) it in a big pot with water at 120C for an hour (x4 times). That wood leached so much tannin that the bucket water looked like strong coffee when the sterilizing run was done. It finally got to the "tea" stage. The neat thing was the sterilization gave the entire piece a very deep, rich, brown tone. I put it into my tank and it's working great. Very minor water water discoloration that I can only tell if I drain some tank water into a white bucket. No more sap. Tank pH dropped to 6.6 from it's usual 6.8. I did have fungal growth and what looked like slime mold last week growing on the wood, but it's clearing up very nicely now and is almost gone. My BN plecos seemed to actually like the fungi stuff and the _really _like the mopani wood.

Conclusion - I'd recommend large pieces of mopani wood for a tank, but only if you have time, energy, and a big enough pot to really boil the heck out of it repeatedly! I can't imagine how dark my tank would have been from tannins without the autoclaving. If you want tannins, mopani's the way to go.


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## Byron (Mar 7, 2009)

The fungus is the real issue with Mopani. Sometimes you can cure it, sometimes not. There are many types of fungus that can occur on this and other wood, so what works once may not again.

I personally will never buy this wood again. I nearly lost fish the first time, and after I too had boiled/scrubbed it to where it appeared OK, several months later the white fungus reappeared and I didn't notice it on the back until several fish mysteriously died. The wood went out to the garden.

I also know of others with dead corys from this fungus. Be careful.


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## DKRST (Jan 11, 2011)

Thanks Byron. After the pressure-sterilization process, the only possible source of my fungus/fungi is from the tank environment itself. There may be something about mopani wood in particular, a sugar in the sap, or something else that promotes fungal growth. I am confident, in my case at least, that this fungus is from my tank's environment, not "imported" with the wood. Having said that, that does not mean a "native" fungal bloom could not potentially cause problems in a tank! 

Always good to keep a close eye on anything new in a tank - Buyer beware...


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