Can’t keep pH up in a new tank!!

[Virginia Reef]

I have 2 new tanks (couple of weeks). All LR and LS came from two other tanks established over 2 years each. Had a minimal cycle-ammonia peaked at about .25 to .50 and nitrite never showed a reading. I have been adding Kalk several times a day for several days. The pH rises as much as .2 but always seems to fall back to its previous level. I have also used Kent pH buffer a couple of times. I use DI water with Kent Salt. All of the livestock seems healthy except for the newest arrival- the Blue Hippo Tang. He appears to have a small case of ich. Just got him 48 hours ago by mail with the cleanup guys.

Should I be concerned about the low pH? Will it rise as the LR and/or LS contribute? I plan to add a drip system to the 90g system to dose Kalk rather than add it in larger amounts manually. What else can/should I do?

The 55g is only to hold the LR till the hair algae disappears. I plan to add the LR and all livestock to the 90g at a later time.

Following are my two setups:

Size: 90g
LR: 95lb
LS: 50lb Live Caribsea Aragonite on top of 150lb new Southdown & 40lb new Caribsea Aragonite
Temp: 79
Salinity: 1.0235
Calcium: 350
Alkalinity: 180
PH: 8.0
Fish: Midas Blenny, Orchid Dottyback, 2 Percula Clowns with host Anemone
Inverts: 50 Astrea Turbos, 40 Hermits, Coral Banded Shrimp, Peppermint Shrimp, 2 emerald crabs
Coral: Plate, Open Brain, Bubble, Candy Cane, Pipe Organ, Clove, Zoanthids, and Mushrooms
Filtration: Seaclone Skimmer in sump, return pump, 2 power heads with wavemaker in tank
Lighting: 2x175watt MH 10,000K, 2X65watt PC Actinic

Size: 55g
LR: 70lb with hair algae
LS: No substrate
Temp: 80
Salinity: 1.0235
Calcium: 350
Alkalinity: ?
PH: 8.0
Fish: Blue Hippo Tang
Inverts: 50 Astrea Turbos, 65 Blue Leg Hermits, Small Hitchhiker Crab (emerald?), Lettuce Nudibranch
Coral: Couple of stray Zoanthids
Filtration: 2 power heads in tank
Lighting: 2x25wattfluorescent

[the_blue_tuna]

You might want to try a different pH test. Is the test you have now old/outdated or somehow contaminated?

[Ritteri&Bubbles]

Low PH???? a PH of 8.0 is fine. And actually your PH can swing from a low of 7.8 to about 8.5 roughly. The mornings is would normally be a bit lower than after the lights have been on all day, as photosynthetic activity naturally raises PH. PH is one of the last things I would worry about in a reef tank unless it is seriously out of the range I gave you. What I would do would be to raise up your salinity to around 1.025-1.026 which is much closer to natural strength sea water. Bring you calcium up to about 425-450ppm and make sure you Alk is around 8dKH. I am not sure I understand your 180 alkalinity reading, but Alkalinity is normally measured as dKH or meq/l . Your temperature is fine and everything else looks ok. All I would worry about is the Calcium and alkalinity.

[Virginia Reef]

I am using a pH meter. Im believe that my test strips for alkalinity are expressed as dKH divided by meq/l. Anyway, the 180 is where it should be according to the test strips.

Thanks for your comments.

[bongobrian]

dripping kalk will help raise and stabalize the ph. A refugium would also help. Have you tried any ph buffers? whenever my ph gets too low, I use a ph buffer to bring it back up.

[stang69]

Also if I may add be sure you have suface agitation so as to aid in the exchange of gasses.


Jeff

[Virginia Reef]

I have been adding both pH buffer and kalk. I hope to set up a kalk drip in the next day or two-so far been adding manually a couple times per day.

Surface agitation seems good to me. I have the return from the sump directed along the surface.

The buffer and kalk raise pH temporarily but it always drops back to previous levels. I haven't been able to get it to hold above 8.0.

Based on some of the earlier posts, I'm going to stop sweating the 8.0 reading. Maybe the kalk drip will help. If not, oh well. Everything looks really great in the tank.

[bongobrian]

Is the ph problem in the 90 gallon or the 55? I noticed you don't have a reading on your alk for the 55 gallon and your reading for the 90 gallon is rather odd... 180?? what unit of measurement is that? the typical units are usually meq/l or dkh and 180 wouldn't match either of those scales. Anyway, if your alkalinity is off it could be causing a buffering problem in your system. Just a thought.