Does Hydroton float?

[George Hall]

I know it's suppose to be lightweight and all but is it suppose to float? I used a 100 gallon stock tank and put a few inches of river rock on the bottom, I planned on adding 12" of Hydroton. So far I put in a 50 liter bag and the Hydroton keeps rising with the water, do they need to get good and soaked before they stay put or what?

[TCLynx]

It will tend to sink as it becomes saturated but in general you are not supposed to flood the bed deep enough to float it in the first place.  You want to leave the top inch or tow of media above the flood level and until you fill the bed up you may see some floating hyrdoton.

[George Hall]

Ok thanks, I'm not finished yet I need at least another 50 liter bag but it seems that if I did have the media right at the water line then add another 2-3" the media would still rise with the water, like enough to almost cover the bell.

[TCLynx]

generally if you have the media a couple inches above the high water line, it will be heavy enough to stay down, especially as the stuff in the lower regions becomes saturated.  If you were to leave the bed flooded and filled with media for a day or two you will find that the stuff down below won't tend to float as much after a while.

[Jon Parr]

I've had it float for over a week. Thought it smart once to use it as fish tank gravel, most of it floated immediately and for a few days. After a week or so, I scooped out the floaters, assuming the sinkers must surely be saturated and stay down, right? Wrong. Some of the sinkers were neutral, causing them to sink, but would float again if stirred up, as in when a startled tilapia kicks it's tail. Some would drift lazily through midwater, kind of odd to watch rocks floating about.

[RupertofOZ]

Was it genuine "hydrotron" Jon... or a generic brand....

 

Sounds like it could be the cheap "chinese" brand...

[Jon Parr]

Name brand Hydroton, made in Germany, indeed, Rupe. I don't consider floating media a flaw, though, just not suitable for aquarium substrates. No floating problems with flood and drain, as long as the top is dry.