Are These Little Round Things Some Kind Of Eggs

[Fishmanic]

I noticed a few of these yesterday and scooped them out with a net and threw them out thinking they were snails.  I saw several more today and picked one up and took a closer look.  It was totally round and beige colored and about 1/16 inch in diameter.  My tanks stocking in the 29 gallon tank is in my sig.  
 
 
If they are eggs, which fish could they be from?
 
http/images47.fotki.com/v763/photos/1/1043660/4377500/IMG_0456-vi.jpg
http/images15.fotki.com/v235/photos/1/1043660/4377500/IMG_0459-vi.jpg

 

[Munroco]

They look a bit big to be eggs, try squashing one.

 

[Fishmanic]

they have a fairly hard outer shell and soft on the inside---could it be some kind of seed?  the only thing I added to the tank recently was a java fern from my other tank and a rock which I poured boiling water on a few days ago---could they be eggs that maybe were  laid on the java fern from the other tank?  see types of fish in the other 35 gal tank in my sig

 

[betta fish]

Have you used any fertiliser pellets in your sand such as these? https/encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcTPWAwvedOycVThkd-cFCus87RFD83-jl8aENHdav9G3O29ClbA

 

[Baccus]

They look suspiciously like slow release fertilizer like Osmocote
http/www.everris.com/Home/Ornamental-Horticulture/Products/Brand/Specialty-Fertilizers/CRF/Osmocote/Osmocote-Pro

the best picture I could find of Osmocote for you to compare with your mystery balls.

 

[Fishmanic]

BINGO. Mystery solved. Yes i did put in a few osmocote pellets several week ago. Musta rose to the top od the sand

 

[Fishmanic]

Seems like some of the fertilizer pellets have disappeared. I'm thinking the rams may have eaten them. Could they be harmed by this. They appear to be fine at the moment

 

[Baccus]

If the fish seem fine then hopefully the eating of some fertilizer wont hurt them.
In future maybe look at using something safe like rabbit or dried sheep/ goat droppings. The bonus of this is they are pre-pelleted and totally organic. Personally I would go with rabbit droppings, because any sheep or goat has the potential to have had worming drenches in their digestive systems.
Or you could get fish tank dedicated plant fertilizer tablets which can be put under the substrate near the plants roots.

 

[Ltygress]

FYI, rabbits can have dewormer in their system too. Ivermectin is used to treat wry neck, and wazine is used to treat pinworms.

I used to breed rabbits and always had these and tetracycline on hand.