Hi

I have what I think are some odd things happening in my tank.

I have a 125 litre planted tank with a Sera Seramic PH controller connected to a Sera co2 system

The PH Controller has been bought second hand and its my first so Im not sure whats happening is correct or not. Im trying to stabilise a Ph of 6.5 but odd things happen in my tank. When the lights come on the Ph will drop to about 5.9 and steadily creep up during the day to maybe 6.1. When the lights go off at night the ph then shoots up past the 6.5 limit and the controller then starts injecting co2 overnight keeping it around 6.5. As soon as the lights come on again in the morning the ph drops again to 5.9 ish????

Is this normal? I would have thought that with the plants pearling all day the ph would be rising during daylight hours thus needing co2 injection?

Everything else in the tank seems ok and the plants are growing fine.

Kh is 5, Gh 3 and the ph probe has been calibrated ok with the test fluids.

Anyone have any ideas? PS, I havent tried a different probe yet as this would involve buying a new one :-(

thanks

Stu

Sworrall,

Why are you injecting CO2 at night? You should be injecting CO2 during
lighted hours in order to facilitate photosynthesis. At night, plants
go into respiration in which they use oxygen instead of CO2. When you
inject CO2 into the tank, your PH will drop because CO2 creates
carbonic acid, which will bring down your PH. If you do not want your
PH to drop, you may wish to add a buffering agent, or you may wish to
do more frequent water changes, though based on your GH and KH, water
changes aren't really going to help you much.

....as I read your post again, it sounds like the problem you are having
is that as soon as the lights go on, your PH reading changes and this
also occurs as soon as you turn the lights off. If this correct? If it
is, I would hazard that your PH meter is faulty.

Hope something that I said helps, but I'm no expert so maybe someone
else can offer better advice.

When you have a ph controller you let that control the dosing of co2 so you leave the co2 open 24/7. When I didnt have a contrller the co2 would shut off at night with the lights via a solenoid. I have been told and the instructions state that with a controller you let that control the dosing all day and night.

I think in theory the co2 wouldnt usually run at night when using a controller due to fish respiration etc. this is why I have a problem in that the ph rises at night and falls in the day.

stu

In article ,
says...

Hi

I have what I think are some odd things happening in my tank.
... When the lights come on the Ph
will drop to about 5.9 and steadily creep up during the day to maybe
6.1. When the lights go off at night the ph then shoots up past the 6.5
limit and the controller then starts injecting co2 overnight keeping it
around 6.5. As soon as the lights come on again in the morning the ph
drops again to 5.9 ish????


Is it possible that some electrical interference from your lights is influencing
the pH measurement ? I suggest a quick test. While watching the pH readout on your
controller, turn the lights on and off. Is there an instantaneous change in the
reading ? If so, then there is an influence on the pH measurement due to the
lights that will cause problems.

A while back I experienced this with a handheld pH meter and power compact lamps
with an electronic ballast. I posted on the subject and others said that there was
no problem with their controller. The Sera is not as common though. Nobody with a
Sera responded to the post, and your installation could be more sensitive.

If you find this to be the problem, one thing that you could try would be to
separate the pH probe and cable from the lighting wires and ballast. Also, try
grounding the reflector(s). If the reflector is a problem, you will be able to see
a change in pH readout when you touch it. When you have it solved there should be
no change in displayed pH when the lights are turned on or off.

Hello,

I am sure many of you have heard on how rec.ponds was totally destroyed by
a vendetta.

Even the regulars don\'t participate like they use to. And many of the
ponder have migrated elsewhere here is a solution;
a moderated group to eliminate all the fuss, That Reel Mckoi and Jabriol
has brought to rec.ponds

The choice is yours; you can participte in your hobby, without the need of
updating your filters, or you can can post hoping that no one will forge
your e-maill address and land you in a kill file or filter.
Everyone can read from the group, but only members in goodstanding can
post.

Here is the information:


About The_pond

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spam from you know...

Categories: Language: English

URL
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Email




Joe the lurker


*** Sent From/Enviado desde: http://groups.expo.st ***

pondmeister wrote:
Hello,

I am sure many of you have heard on how rec.ponds was totally destroyed
by a vendetta.

Even the regulars don\'t participate like they use to. And many of the
ponder have migrated elsewhere here is a solution; a moderated group to
eliminate all the fuss, That Reel Mckoi and Jabriol has brought to
rec.ponds

The choice is yours; you can participte in your hobby, without the need
of updating your filters, or you can can post hoping that no one will
forge your e-maill address and land you in a kill file or filter.
Everyone can read from the group, but only members in goodstanding can
post.

Here is the information:


About The_pond
Description: A group dedicated to real ponders without the crosspsting
spam from you know...
Categories: Language: English

URL
http://groups.google.com/group/The_Pond
Email



Joe the lurker


*** Sent From/Enviado desde: http://groups.expo.st ***


This group is a joke. The first post is by Reel McKoi.

--
Elaine T __
http://eethomp.com/fish.html '__
rec.aquaria.* FAQ http://faq.thekrib.com

Hi Elaine and all,

Carol was allowed to make one post so that her IP can be identified and
thus banned. This mean that she can not nym-shift to try to subscribe.
She has been banned from the group. Jabriol has not made an attempt. In
any case the group is managed now by Kathy from AOL.

That being said, the group is what you make of it. REc.ponds is being
destroyed by Carol. Take a look. This will not happen in the new group.



Elaine T wrote:


This group is a joke. The first post is by Reel McKoi.

That sounds all very democratic,
Sort of "one post and your out" or the "last post"
This woman sounds like someone you would hire to demolish a house,
bit like one of my X,s mothers.. O-god, don't ask, But I must say, she did
have a shave before I got a little kiss.
bassett

wrote in message
oups.com...
Hi Elaine and all,

Carol was allowed to make one post so that her IP can be identified and
thus banned. This mean that she can not nym-shift to try to subscribe.
She has been banned from the group. Jabriol has not made an attempt. In
any case the group is managed now by Kathy from AOL.

That being said, the group is what you make of it. REc.ponds is being
destroyed by Carol. Take a look. This will not happen in the new group.



Elaine T wrote:


This group is a joke. The first post is by Reel McKoi.