need help with low ph and calc react & kalk reactor

[SALTWATERSIG]

i've been battling with my ph ...i am running a mrc dual canister calc reactor also have pm kalk reactor dosing with litermeterIII .
i use my litermeter to dose appx 2 3/4 gallons of limewater per day (equals same amount of daily evaporation) and i can maintain ph of 8.09 during lights on period and ph of 7.75-7.8 at lowest point of lights off period. but i can only achieve that if my calc reactor is dripping like 1 drop every 3 seconds and co2 bubble every 12 seconds so ph in second chamber is way too low. if i increase eflluent drip to appx 2 drops per second , the effluent ph from 2nd chamber is appx 7.2 where according to manufacturer guide says it should be......but then my ph at night drops below 7.7 and only gets as high as 8.0.

my photo period is appx 10 hours of t5's and 8 hours of mh. i also run my refugium 24/7 with 52 watts of pc over cheato.

any suggestions. by the way i just calibrated the ph probe.

100gal tank with 30 gal sump/refugium

[SALTWATERSIG]

just wanted to add that i am planning to change refugium lighting to a 100 watt bulb instead of 56 watt pc's.

[bertoni]

With what solutions was the pH probe calibrated? Have you tried the aeration test discussed in this article:

http://www.reefkeeping.com/issues/2004-09/rhf/index.php

More aeration might help. Does the tank have a skimmer?

A reverse-lit refugium might be more useful. I'm not sure, though, how much light is too much for 24x7 lighting.

[SALTWATERSIG]

yep..i'm running a skimmer and i calibrated with 7 and 10 solutions. i do have an old probe that i'll try to see if there is any diff as well.

[bertoni]

What brand of solutions? Some aren't reliable. Those are the correct pH levels. The pH you gave is low, but not that uncommon for tanks with a CO₂ reactor.

You might try feeding the reactor output to the skimmer, if possible.

[SALTWATERSIG]

i don't recall who the solutions are made by but i'll chk when i get home. i do have effluent line dripping into sump right above area where skimmer pump is at and i have limewater dosing right after skimmer before it enters refugium (after that is where my return pump is at).

[SALTWATERSIG]

last night i switched from 56watt pc to 100watt bulb over refugium and wished for the best over night. when my t5's turned off @ 11:00 pm last night ph was @ 8.0......@ 5:30 am ph was @ 7.69 so i added some limewater sludge to increase ph.
i am going to try a diff bulb tonight maybe 125 - 150 wattage.
also turned off calc reactor last nite as to not bring down ph even more. my ultimate goal is to get ph to stabilize and rise so that ph doesnt drop below 7.8 at nite and then put calc reactor back online.

[SALTWATERSIG]

man i am starting to hate this hobby! came home today and found ph monitor showing 7.86 so i switched out ph probe with old one i had to compare and after calibrating for what seemed an eternity i had ph reading of 8.13 then i switched ph monitor with an extra one that i had and pinpoint showed 7.56 (i again recalibrated prior to reading) and the other probe 7.65 , i dont know what to do.....my alk is still at 10.56 dkh and i'm not even using calcium reactor. not sure what is bringing down ph....use to think it was my calcium reactor .

[bertoni]

I'm not sure the pH is that low. I don't trust the pH monitor at this point. 7.56 shouldn't be possible without a lot of carbon dioxide buildup. Can you open the windows for a few hours and get some fans pushing air over the tank?

[SALTWATERSIG]

you were right bertoni.....i purchased another probe and after recalibrating .....7.91 as of 6:30 pm . i also took apart my 2 tunze 6060's and soaked in vinegar, one seemed ok but the other was sort of gunked up around screen and on the prop shaft. hooked them back up and now putting out quite a bit more power.

[bertoni]

Sounds good!