Blackish spots on Java Ferns (some leaves) only.

[grey_fox]

Ok, now that's a nut-buster...

My PH in the tank is currently @ 6.6. So Alan, for your case, when the JFs are in the pond, those growing in there do not get those black spots?

[alanyeo99]

The spots disappeared after about 1 month in my pond. And the leaves turned beautiful light-green. btw, pond PH is 5.5. Anybody can confirm PH is the cause???

[black17]

Hi guys, my ph is 6.5 - 7. Can't give exact readings because I'm using the Hagen ph test. Extremely hard to compare result colours. But note that the spots do not spread to other nanas or JFs. Its restricted to a particular bunch.

[grey_fox]

I've snipped off most of the blackend leaves and did notice this particular leaf. Half of it was covered by another Java Fern leaf and only half was speckled with that black spot. The other half which is not covered is fine.

Lighting (high intensity) or PH issue now?

[grey_fox]

OK, seems that no one has any idea.

I'm about to do a test to my tank. Decided to have only 4 x T5HOs used during photo period and a shorter photo period as well, reduced by 1 hour. CO2 has no change at all.

Lighting used now will be 2 x 10,000K & 2 x 6,500K bulbs @ only 1.4WPG

*crosses fingers*

[black17]

Please report your findings Grey Fox. Thanks.