# osmocote in the aquarium



## Dan-CR4 (18 Aug 2014)

I got some osmocote and wondered if its ok in the aquarium, the label says http://www.lovethegarden.com/system...t/label/01-13/os-controlled-release-label.pdf

if u read that link it tells u a bit about it. I was thinking of putting some in the substrate.  any help is appreciated.


----------



## ian_m (18 Aug 2014)

Be careful, if not don't use at all, as it contains ammonia (usually ammonium nitrate) which is highly toxic to fish. Absolutely fine if plants only, but likely a no no with fish around.


----------



## dw1305 (18 Aug 2014)

Hi all,
Osmocote and similar products are "Controlled Release Fertilisers". The nutrients they contain are in a soluble form, just like the ones we use for EI, but are encased in a resin coat that means that they leak out slowly over time.

The coating is designed to release nutrients more quickly in warm, wet conditions, because this is when the plants will be in active growth.

The two problems for aquarists are the ones that the label mention, conditions in our tanks are by definition warm and wet, and that the nitrogen source is ammonium nitrate (NH3NO3), because it combines solubility with a high nitrogen content.

If you add a small amount to the substrate it should be all right, particularly if you have humus and or clays with a high CEC, but if you add too much, NH3 may prove toxic to your livestock.

cheers Darrel


----------



## Vazkez (18 Aug 2014)

Hi guys 

Thank you both. I was just about to ask if I can use this for DIY tabs just to keep my hands busy.








But I know my answer now. I can't as there is ammonium N present.


----------



## Vazkez (18 Aug 2014)

Hi guys 

Thank you both. I was just about to ask if I can use this for DIY tabs just to keep my hands busy.







But I know my answer now. I can't as there is ammonium N present.


----------



## dw1305 (18 Aug 2014)

Hi all,





Vazkez said:


> But I know my answer now. I can't as there is ammonium N present.


 Yes pretty much, in this case the "ureic nitrogen" (urea - CO(NH2)2) is 46% N and will be converted to NH3 by micro-organisms with the urease enzyme, so it will end up as ammonium nitrogen eventually.  Once or twice I've used these sorts of liquid feeds as tank fertilisers, but only at very low dosages. Also I keep very weedy tanks and always have a lot of dissolved oxygen. I definitely wouldn't recommend it.

cheers Darrel


----------



## Dan-CR4 (18 Aug 2014)

I was thinking of putting some in some ice cubes at certain points around the tank, buried at the bottom of the substrate.

anyone got any ideas what we can use, as I have seen that some people use osmocote plus, but can never seem to see this available in the uk


----------

