Carbonate Buildup on Media

[Arwen Vaughan]

I am curious what you guys do to get the carbonate buildup off of your hydroton or other grow medium, or even keep it from building up in the first place? It seems to build up on the top layer of media as the water wicks and evaporates off the surface...leaving white crusty stuff. Also, I have noticed that it really irritates the skin like salt when you try to dig it out. Is the water level below the surface of the media too high? I think I have too much calcium carbinte in the system, but how do I remove it? Any ideas would be much appreciated.

[Brent Shafer]

I have some on my media, but i dont worry about it.  

The water test kit shows in line with where I want to be. If you are "digging" in your beds are you cleaning them out and letting them re-cycle? how big are your beds and FT?

[Arwen Vaughan]

Thanks for the post. I just been removing the media with calcium carbonate crusted on it. I don't know how to remove it effectively, so it is just sitting in 5 gallon buckets. My water is not inline and the pH is too high (7.6) normally. I am trying to figure out how to get it down into the slightly below 7 sweet spot. I stopped adding calcium months ago, but still not happening. Thanks for the comments though. I'll let you know how it goes over time.

[Brent Shafer]

7.6 pH is not horrible : )  I add white vinegar to the GBs to lower pH. But I would need to know the size of your system to recommend the dosage? And if you could share your other water test results it may point to something.

[Arwen Vaughan]

White vinegar really? Interesting.  My system is a 275 gallon IBC tote system. So, it is roughly a 4 x 4 foot grow bed with about 200 gallons of water in the fish tank.

My water stays around 70 degrees, 7.6 pH, 20 Calcium hardness, 0 amonia, 0 nitrite, and off the scale nitrates. That is all the metrics I take regularly. The system has been running for around 3 years straight.

[George]

Someone correct me if I'm wrong but I believe vinegar kills bacteria, which you don't want in an aquaponics system.  

Brent Shafer said:

 I add white vinegar to the GBs to lower pH. 

[George]

PH should naturally fall in an aquaponics system due to nitrification.  Generally, it's necessary to raise PH, not lower it so something in your system is abnormally affecting your PH.  If you search Vlad's topics, you'll find one on a bad batch of hydroton.  Perhaps the media is the cause of your PH problem.  

Normally, a media bed has a dry layer on top, two inches or so.  If you have such a dry layer, then you shouldn't also have white crusty stuff on the media surface.