Hydroton beads

[mary proctor]

The only trouble we had with one of our systems using Hydroton beads was growing 4 tomatoe plants in one bed and 5 tomatoe plants in the other bed to one tank system.  We lost almost all of our hybrid fish in this tank.  Everything with the water was fine, no problems, we continuely checked the PH, Nitrate, Nitrite, amnonia, etc.  Abundant air.... clean water from filtration.  We still are a a lost on why we lost our fish in this one system.   None of the other 5....2 bed systems had a problem.  We had noticed that you can no longer get the German hydroton beads.  Just the American made???comments anyone  Mary

[marvin]

the pit where clay for hydroton was being harvested is dried up. Alot of hydroponic and specialty garden shops are on back order for hydroton and in some cases have stoped carying it completly. Although ebay has an abundent supply of hydroton, the hydro shop near me has switched over to growstones. Which is recycled glass product, and should eliminate ph swings.

[Eric Warwick]

Hydroton is pH inert as well.

marvin said:

...the hydro shop near me has switched over to growstones. Which is recycled glass product, and should eliminate ph swings.

[Eric Warwick]

I'm not exactly sure what you're asking, but I'd consider what I think your question is (is the non-german hydroton, or hydroton killing my fish?). The answer would be correlation=/= causation. Just because one variable was different, when more variables could be at play, does not mean that one variable caused it. Were your fish acting strange in the lead up to their death? If they were it could be disease. I'm not a fish expert, so maybe if someone with more experience with fish care could try to isolate the problem that would be great. Try testing your testing kit. It may have been defective.

What was the water temperature?

What species was it? 

What strain was it?

How many fish?

What were you feeding them?

Did any noxious chemicals come into contact with your system? These are all things we need to know. Please answer what you can.

[Vlad Jovanovic]

Hmm...interesting. I wonder just how toxic tomato plant roots are to fish..?

[Jon Parr]

Hi Mary. I too missed the question.

Vlad, nightshade family does indeed have some toxicity, but I regularly feed my tomato plant leaves, stems, and roots to fish, chickens, and rabbits. No problems. I used to root broken tomato stems in the bubble-stream of my tilapia fry tank (so effective it's scary, I have 4" long mass of roots today on a stem broken off on Friday), but the fry soon figured out they liked the roots, and ate them up, including the green outer layer of stem. Again, no problems.

[Vlad Jovanovic]

Cool...I was just wondering, as the 'tomato toxicity question' seems to come up from time to time...and there are known lethal doses of tomatine for fish...on the other hand, at lower doses it is being explored, successfully, (in trout) as a way to stave off tumors...How this translates into real life situations is beyond me..? As far as I'm concerned Jon, your post pretty much put any worries I had to rest. Thanks.

Mary, what is (plants) in the other 5 'identical' separate systems out of curiosity? How bout the media in those other systems?

[marvin]

The firing process is suppost to make the clay ph inert. But I have seen first hand that even rinsing untill clear runoff isnt always enough. It will cause ph rise for a day or two. Especially if it was stored for long period. Not familar with american product but havent heard anything good about it. Mary said the ph was fine when tested , which posiably is tropical fish may be more sensative to nitrate levels which were to high for that species.? or posiable disease but im no fish expert

[Eric Warwick]

What is the pH of your water after sitting for a couple of days (to outgas Cl) in pH inert glass?

marvin said:

The firing process is suppost to make the clay ph inert. But I have seen first hand that even rinsing untill clear runoff isnt always enough. It will cause ph rise for a day or two. Especially if it was stored for long period. Not familar with american product but havent heard anything good about it. Mary said the ph was fine when tested , which posiably is tropical fish may be more sensative to nitrate levels which were to high for that species.? or posiable disease but im no fish expert

[Vlad Jovanovic]

Eric that's a really good question. Just FYI though, in terms of the "false low" pH reading that you get right out of the tap...it's the CO2 trapped in the water that is the culprit and not Cl. (Eric, Cl has a pretty high pH of 11 point something, so it could never be that. It's good to off gas Cl for other reasons though).

Carbon dioxide is only water soluble when pressure is maintained (like in your water pipes). In this dissolved state it is called carbonic acid H2CO3. Since it is a weak acid, when you measure water right from the tap without letting it sit out for a day or so, it will give you a false low pH reading. Once the the carbonic acid has a chance to off-gas into CO2, and escape into the air, you can only then measure the pH and confidently obtain a realistic reading. The difference is pretty big too. One to one and a half pH points (or more) is no small matter. If anyone cares this is the relation...

 

CO2 + H2O --> H2CO3

After that the carbonic acid reacts slightly (and reversibly) in the water to form a hydronium cation H3O-+ and the bicarbonate ion HCO3-

H2CO3 + H2O --> HCO3- + H3O+

This is also why when you open a bottle of distilled water, first you can't zero in on a reading (distilled water having no ions and all, and therefore no determinable pH. But, then as the distilled water reacts with the CO2 in the air pH you can hone in on a somewhat stable reading and will always get an acidic one (barring any other contaminates). This caused me no end of grief for a few days a good while back in my college days...having always heard, and believed, that distilled water has a pH of 7...This is not true. the pH of distilled or demi water is "indeterminable"...Anyways.............

The chemistry probably only interest Eric, but anyone reading this (ever) needs to know that you have to let your sample water (tapwater, well water...anything that's been in a pipe or through pipeworks) sit out for a day or so before testing it's pH. If you don't, in a day or two you'll be scratching your head wondering what is causing your waters pH to "rise"...

 

 

Eric Warwick said:

What is the pH of your water after sitting for a couple of days (to outgas Cl) in pH inert glass?

marvin said:

The firing process is suppost to make the clay ph inert. But I have seen first hand that even rinsing untill clear runoff isnt always enough. It will cause ph rise for a day or two. Especially if it was stored for long period. Not familar with american product but havent heard anything good about it. Mary said the ph was fine when tested , which posiably is tropical fish may be more sensative to nitrate levels which were to high for that species.? or posiable disease but im no fish expert

[marvin]

K ... My only experiance with hydrotron was with hydroponics. I run a ro/di filter from the.filterguys. Which removes the chlorine as well. Then it goes into 50 gallon res. With bubbler. I only run hydroponics during winter time and change waer source. Think I was sy

[marvin]

Srry on mobile , around 6.2 I run stacked and or vertical units. Would love to incorporate this in aquaponics. I have greenbouse and agriculture experiance, as well as aquaculture experiance. So this will be perfect fit for me. Have some aquaponics books coming. If anyone could recomend and good up to date complete aquponics guide .... That would be great

[Jon Parr]

I care about the chem, Vlad. And it should settle the fog for any trying to filter thru opinion and fact on open forums. I didn't know that about distilled water (or I had forgot), and it makes sense. I know that planted aquarium enthusiast inject CO2, both for plant growth, and pH control. The device made for injecting regulates CO2 with a pH meter, injecting more CO2 if pH raises. This is in fact a very stable way of maintaining perfect pH without the use of acids, and the CO2 off gassing will benefit your GB plants as well. The pH influence of CO2 is also pronounced in tanks that have a lot of algae, or do not cycle in the dark hours. Algae nets an O2 surplus during light, but every living thing breaths O2 and CO2 levels rise during the night. Point being to measure your pH at the same time of day for an accurate reading.
When I was choosing gravel for my beds, I got a sample of every suitably sized rock that my local rockery had. I half-filled 1 qt mason jars with different media, added water until full, and measured pH every day for at least a week. Jut for control, one jar had hydroton, and one had only water. The hydroton matched the pH of the water only jar for the whole test (as did the river gravel I chose)