The experiment was to increase my PH at night and narrow the swing between day and night.
Aquarium D-D 1500 pro reef.
Equipment in sump Turbo Aquatics ATS, Reef Octo skimmer, Ultrareef reactor with a small amount of Rowa. Oxydator A with 12% hydrogen peroxide and 2 catalysts. 2 bio blocks.
The tank is well stocked with lots of small.fish, SPS frags, some colonies and LPS corals.
Feeding is 3 often 4 times per day
Problem. My PH would drop to around 7.7 at night and climb to around 8.1 at peak lighting times. Not ideal for growth or health of corals.
I wanted a simple way to increase my PH. My aim was to bring my night time PH to above 8 with daytime to around 8.3
What to use.
The tank is too far away from an outside wall so running an air intake to my skimmer was not an option. I didnt want to use a programmable pump and controller. I wanted something simple enough and something I was already conversant with.
My choice was good old Kalkwasser which would also help with both KH and Calcium.
Choice.
I played around with various DIY designs before settling on a DIY doser fed from Tunze ATU which I also modified to reduce any chance of over dosing kalk. This was something I had the misfortune to do some years ago.
The method.
I found a plastic container which fitted neatly into my ATO reservoir to house my kalk mixture. The feed from my Tunze ATO was split with a John Guest 2 into one 1/4" connector with 2 taps to divert flow from the ATO. One branch going into the sump directly the other into the kalk container.
The how.
Following the last feeding of the DT about half an hour or so before lights out I turn the feed tap to the kalk reactor to receive RO from the ATO and close the tap from the feed directly to the sump.
This way I am dosing kalk at night only right up until my DT lights come on in the afternoon when the taps are reversed when RO from my ATO once again goes directly into the sump bypassing the kalk reactor.
What else.
Next job was to modify my Tunze ATP sensors. My Tunze comes with 2 sensors, an infrared low level sensor and a float switch sensor to detect over filling. However for me the distance and therefore sensitivity between them was too great for my liking.
I managed to find a new Tunze magnetic sensor holder and moved the mechanical float switch from the the origional sensor holder over to it. Now it's a simple task to have the sensitivity and gap between the optical and mechanical float adjusted.
I am lucky in that my sump level hardly ever changed in water depth a in the weeks I have been using this configuration no alarms from the Tunze have been triggered due to under or over filling of the sump.
Now all I have to do is remember to switch the taps over for each cycle. I admit I have forgotten on a couple of occasions to do this but to no I'll effect other than going back to a larger swing in PH as before but not as much it would seem.
The results.
My PH now before my DT lights come on in the afternoon is 8.3 sometimes as high as 8.4. PH in the afternoon when no kalk is being dosed is around 8.2.
My SPS corals have responded and showing increased growth in the few short weeks I have been running kalk this way.
Improvements
Just a note. I have made a kalk reactor not stirrer. I was thinking of putting a small powerhead in the kalk reactor on a timer but found a Aqua Medic Kalk stirrer I had at the bottom of my workshop I had forgotten about so I am now using that. I am using the stirrer not because my kalk reactor didn't work as intended but it was there and mixed the kalk slurry better and along with a bit of trimming it fitted snugly in my ATO chambers why not use it.
My split Tunze ATO sensors.
Link to my DIY kalk reactor.
www.reef2reef.com
Link to my tank build thread at the bottom of this post.
Aquarium D-D 1500 pro reef.
Equipment in sump Turbo Aquatics ATS, Reef Octo skimmer, Ultrareef reactor with a small amount of Rowa. Oxydator A with 12% hydrogen peroxide and 2 catalysts. 2 bio blocks.
The tank is well stocked with lots of small.fish, SPS frags, some colonies and LPS corals.
Feeding is 3 often 4 times per day
Problem. My PH would drop to around 7.7 at night and climb to around 8.1 at peak lighting times. Not ideal for growth or health of corals.
I wanted a simple way to increase my PH. My aim was to bring my night time PH to above 8 with daytime to around 8.3
What to use.
The tank is too far away from an outside wall so running an air intake to my skimmer was not an option. I didnt want to use a programmable pump and controller. I wanted something simple enough and something I was already conversant with.
My choice was good old Kalkwasser which would also help with both KH and Calcium.
Choice.
I played around with various DIY designs before settling on a DIY doser fed from Tunze ATU which I also modified to reduce any chance of over dosing kalk. This was something I had the misfortune to do some years ago.
The method.
I found a plastic container which fitted neatly into my ATO reservoir to house my kalk mixture. The feed from my Tunze ATO was split with a John Guest 2 into one 1/4" connector with 2 taps to divert flow from the ATO. One branch going into the sump directly the other into the kalk container.
The how.
Following the last feeding of the DT about half an hour or so before lights out I turn the feed tap to the kalk reactor to receive RO from the ATO and close the tap from the feed directly to the sump.
This way I am dosing kalk at night only right up until my DT lights come on in the afternoon when the taps are reversed when RO from my ATO once again goes directly into the sump bypassing the kalk reactor.
What else.
Next job was to modify my Tunze ATP sensors. My Tunze comes with 2 sensors, an infrared low level sensor and a float switch sensor to detect over filling. However for me the distance and therefore sensitivity between them was too great for my liking.
I managed to find a new Tunze magnetic sensor holder and moved the mechanical float switch from the the origional sensor holder over to it. Now it's a simple task to have the sensitivity and gap between the optical and mechanical float adjusted.
I am lucky in that my sump level hardly ever changed in water depth a in the weeks I have been using this configuration no alarms from the Tunze have been triggered due to under or over filling of the sump.
Now all I have to do is remember to switch the taps over for each cycle. I admit I have forgotten on a couple of occasions to do this but to no I'll effect other than going back to a larger swing in PH as before but not as much it would seem.
The results.
My PH now before my DT lights come on in the afternoon is 8.3 sometimes as high as 8.4. PH in the afternoon when no kalk is being dosed is around 8.2.
My SPS corals have responded and showing increased growth in the few short weeks I have been running kalk this way.
Improvements
Just a note. I have made a kalk reactor not stirrer. I was thinking of putting a small powerhead in the kalk reactor on a timer but found a Aqua Medic Kalk stirrer I had at the bottom of my workshop I had forgotten about so I am now using that. I am using the stirrer not because my kalk reactor didn't work as intended but it was there and mixed the kalk slurry better and along with a bit of trimming it fitted snugly in my ATO chambers why not use it.
My split Tunze ATO sensors.
Link to my DIY kalk reactor.
Simple way to help stabilise PH with your kalk stirrer
I have a Aqua Medic Kalk stirrer but I couldn't adequately fit in my sump so made a DIY one more about in another DIY post I will do sometime. Prior to using kalk my PH would be 7.8 before lights on getting up to 8.1 after lights on for a good few hour. I was also having to add calcium as my...
www.reef2reef.com
Link to my tank build thread at the bottom of this post.
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