Ph low

[MikeAndrews]

If using a ph probe make sure it is calibrated. Also check ph at the same time each day if possible. It will fluctuate day-night. Mine goes from 8.3 at nite to 8.1 during day

 

[Alwmh4]

How would you suggest switch over to limewater. If I'm at 7.8 and I use limewater as water change, the ph will swing dramatically right?

 

[Adam Baggett]

Start off with low doses then build them up slowly. Remember the snail wins the race in a salt water fish tank.

 

[Randy Holmes-Farley Verified Community Expert]

How would you suggest switch over to limewater. If I'm at 7.8 and I use limewater as water change, the ph will swing dramatically right?

You cannot change water with it.

Limewater is used to replace evaporated water. So that means something like 1 or 2% of the tank volume each day. Add it very slowly to avoid the pH spike, like with a very slow pump or a dripper. Dripping is a good speed.

 

[Alwmh4]

Oh, gotcha. Thanks!

 

[Alwmh4]

Adding the three ga of just salted RO water won't drop ph in tank? I'd rather ask than kill my critters

 

[Alwmh4]

Co2 scrubber is raising ph by the way. I hooked it up today and within 2 hrs I saw noticiable diff in ph test color

 

[Randy Holmes-Farley Verified Community Expert]

Adding the three ga of just salted RO water won't drop ph in tank? I'd rather ask than kill my critters

Salted?

 

[Alwmh4]

In the water change, the salt water mix I am assuming is about 7. Changing out 3 ga with that low of a ph is my concern. Unless you add limewater to the 3 ga prior to change??

 

[Randy Holmes-Farley Verified Community Expert]

A water change won't have a big impact on tank pH, even if the new salt water is a bit low in pH, but there's also no reason to assume it will be low.

Do not add limewater into new water change water. Too much potential for high pH and precipitation of calcium carbonate.

 

[Alwmh4]

Ok. Thank you. I guess I'm looking at it like too much of an equation

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome.

Happy Reefing.

 

[Alwmh4]

update: ph is holding at 8.2 over past few days. added maybe 1/2-1 cup of lime water over 3 days and a co2 scubber.

next question: What size carbon should I use? Ashamedly I have been using the fluval carbon at petsmart and have recently learned that low grade carbon can contribute to phosphates. So I am looking at the Rox brand. The offer small granules and large. Im also on a cycle of changing carbon once monthly. Have read that maybe every 2 weeks might be better but others say that it is unnecessary. Thoughts?
Where is a good place to get Rox from. Have seen a few places online. Obviously Im thinking the cheaper sites but am open to opinions on the subject.

 

[Alwmh4]

also, mesh or felt bag?

 

[Randy Holmes-Farley Verified Community Expert]

I use the ROX 0.8 in a canister filter.

If you want to use it in a bag, I'd use mesh and make sure the water is being forced through it.

 

[Alwmh4]

Any ideas on how much of the rox premium carbon to use. Calculator says 1 tablespoon but sounds way low. tank is 17 ga. current carbon comes in a bag and looks like about 2 cups worth. I understand that its not the greatest product but seems like amount of rox would be similar

 

[Alwmh4]

Id add macro if I had a refugium. How I long for a refugium. My friends 75 ga tank is so much easier than mine.

 

[Alwmh4]

last post was re beaslbob's post re macro algae

 

[Randy Holmes-Farley Verified Community Expert]

Start low on ROX carbon and increase as needed. If the water is yellowed, adding a bunch all at once might light shock some corals. I use about a cup at a time in my 120 gallon display (300 total gallon ) system.

 

[Alwmh4]

oh wow. so a little does go a long way. im assuming i discontinue this other cheap carbon all together then