Mordenite Zeolite as biological filter media

[ILikeFish]

Recently, I’ve been working on building a sump and it’s finally come time to buy the filter media. I’m going to use mostly sponge, but I was curious about using a zeolite material in place of something like ceramic rings or bio balls.
I’ve read lots about zeolites and understand they act as a magnet trapping ammonia and soluble metals. Due to their incredibly large surface area, I was wondering if this would be a cheaper alternative to ceramic rings. 
 

As I understand it, zeolites trap ammonia for a period of time before needing to be replaced or recharged. What if I didn’t replace or recharge the zeolite and used it to grow BB. Would this work long term the way it makes sense in my head? Does anybody have any experience with anything like this?

[Guppysnail]

The only thing I know about zeolite is it supposedly strips calcium and possibly other things from the water. I looked into it a touch but abandoned it due to my large snail population and the calcium thing. Doesn’t answer your question but I thought it worth mentioning for you to look into. 

[ILikeFish]

On 4/10/2022 at 11:37 AM, Guppysnail said:

The only thing I know about zeolite is it supposedly strips calcium and possibly other things from the water. I looked into it a touch but abandoned it due to my large snail population and the calcium thing. Doesn’t answer your question but I thought it worth mentioning for you to look into. 

I appreciate the reply, I’m not planning snails or shrimp in the tank I’m setting up, so calcium absorption shouldn’t be too big of a problem. I could always supplement it if needed

[Widgets]

This article indicates that it is useful to manage an Ammonia spike, but shouldn't be used full time. There is also disagreement on using it to help start a cycle because it keeps the Ammonia from the bacteria. It also states that a salt solution is needed to release the Ammonia. I don't think it will do what you want.

I do remember years ago the carbon inserts for filters were often a mix of carbon and zeolite.

https://www.thesprucepets.com/using-zeolite-in-aquariums-1380937

[dasaltemelosguy]

I agree with @Widgets. Zeolite is useful stuff but it's probably not ideal for filter media. I always put in the bag with fish being transported to keep down the ammonia.

Its surface area is only 1/4 that of typical ceramic media and only 1/6th that of typical carbon for filters so it really doesn't have that much surface area for good BB growth.

Also, if you ever use aquarium salt, zeolite can return toxic levels of ammonia it had absorbed over the months in just 24 hours as salt releases the stored ammonia in zeolite. Probably not ideal for what you want. 

[ILikeFish]

@Widgets @dasaltemelosguy thanks for the replies. I think y’all are touching on an important point. Despite my confidence that zeolite would serve as a good host to BB. One slip up by adding salt to the tank will nuke it. I think despite my interest in saving money during this build, it will be much safer long term to use ceramic rings

[SandSea]

I dont know about long term zeolite but i use red lava rock in my filters. CHEAP from home depot type of place. I also throw a few on the bottom of the tank for seeding new tanks or to put in my shrimp tank for them to munch on the algae