HELP... yellow spots, brown tips, leaves bending

I think this is a ponytail palm or beaucarnea recurvata.
As you notice the lower leaves have yellow spots while its upper leaves are bending or looks like it was folded or pinched.
The plant was situated before where it receives full intense sun (summer sun) and was doing ok but rainy season came and i noticed that small yellow dots are appearing, i suspected that maybe a sign of rot. So i put it in our porch where it receives diffuse bright sun from a fiber glass ceiling without changing its pot or soil. After a month or so, yellow spots disappeared but the leaves ( younger or the upper portion) are beginning to bend so i brougth it back outside where sun exposure is fr. 10am til 3pm.
Its now a month since i brought it outside and those problems are getting worse.
What shall i do? Should i change its potting soil? Or is the pot a problem (its made of cement) or is it too big for it? (anyway, i don't think pot size or material are the problems because my aunt has the same plant planted just like in the picture and its doing ok.) Shall i fertilize it?
Please help i love this plant and when visitors came they always appreciate it and makes a conversational piece keeping my visitors entertained.

This message was edited Oct 6, 2008 11:58 AM

This message was edited Oct 7, 2008 11:12 PM

other image of it

Your first picture isn't quite clear enough to tell you have a deficiency or rust or something else. Could you take a better close-up of the foliage? If your camera has a macro function make sure to use it. Look on your camera for the symbol shown below.

hope these pictures help

This message was edited Oct 8, 2008 11:32 AM

2nd pic

3rd.

Almost all of its basal leaves have these condition but going towards the center or the younger foliage they are none. But still i am not sure if the the condition gets worse.

looks like some species of rust to me.

Much better pics this time. It now looks like potassium deficiency to me. This site has some great pics of potassium deficiency in palms http://edis.ifas.ufl.edu/EP269 especially this close-up http://edis.ifas.ufl.edu/LyraEDISServlet?command=getImageDetail&image_soid=FIGURE%2013&document_soid=EP269&document_version=48150 If this is the case, a well-balanced palm/houseplant fertilizer should clear it up.

Just in case it is rust, check the back side of the affected leaves for a rust-colored powder. For this problem you'd have to treat it with a specific fungicide.

Thank you so much, now i am aware of K deficiency and gain knowledge about Mg def too. However it is negative of rust (that i am aware of and constantly checking for it for my plants and treating immediately).
I believe this is a sign of K deficiency (also potting mixture use is more of sandy). I never fertilize since acquiring this plant (a year now). My aunt who has the same but healthy one fertilized it with slow release balance fertilizer, so i'll use the same fertilizer. Wish me luck. I'll be posting results about it.

Thank you...

the circular yellow areas look like fungal spores to me. low K causes yellowing of the veins, this looks circular and there isn't a micro or macro nutrient def. thats circular and yellow. Looks like pustuales like Jasper said. See if those are slightly raiised.

also, remember fungus is in the leaf, what you see outside is a result of the fungus, you may not always be able to scratch it off or see it on both upper and lower sides of the leave depending on type and age of disease, it's fungus and gone with no treatment it will worsen and possible die, the fungus is setting up a network likea spider web inside the leaves.