# WARNING - solenoid valve failure



## Hidronium (May 10, 2005)

I have just learned that Mr. Antonio Trias, one of the most knowledgeable acuarists in Spain has had a catastrophy in his unique Discus tank.

He left for a short 5 day trip and when he returned pH was 5.2 and all fish was dead. Including rare breeding couple of 2 green wild discus. The solenoid valve failed and remained open, CO2 raised to 250ppm.

He had been using the valve for 11 years, but still it should not have failed...

If you have these valves and delicate fish, make sure you have 2 valves in series to avoid such a catastrophy.

Regards Hidronium.


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## JanS (Apr 14, 2004)

Ouch! I guess in a case like that a controller wouldn't have even done any good.


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## Praxx42 (Mar 4, 2005)

Been there. Not fun.  I doubt I lost as much as he did, but still...


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## Laith (Sep 4, 2004)

Interesting.

I would have thought that solenoids would fail into "off" mode, cutting off CO2?

And with a controller, the electricity would have been cut off to the solenoid once a certain pH has been reached. A solenoid with no electricity will cut off CO2. Maybe it jammed open somehow?

Would like to know more how this happened...


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## shalu (Oct 1, 2004)

Sorry it happened.

However, if mine failed, nothing is going to happen to my discus. Why? I don't use really high CO2 bubble rate just because I have a controller. I fine tune my CO2 flow rate such that it is just enough to achieve the CO2 level I want. This is one case using a controller can be more detrimental than without, if no precaution is taken.

To achieve 250ppm CO2, the bubble rate has to be crazily high.


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## stvolkers (Jan 3, 2005)

True the valve with a spring return, that most have, should have failed closed. No current spring closes no gas flow. But any electrical/mechanical device can fail. An old one also. Sorry that Murffys law hit. Duals and a controller may have helped.


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## Macbrush (Mar 29, 2004)

I have a 1000L tank, so I use an pressurised external diffusor, similar to Dupla S. I connect the pump to the controller as well as the soleniod valve to avoid such disaster.

I had a soleniod failed once, part of soleniod melted and it was jammed open. Lucky I found out as soon as pH dropped just 0.5 below normal.


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