Chemistry: Low pH, Low dK, High Calcium

[ronin33]

Been a while since I was on the site. Took advice and slowed things down a bit. I have a 90 gallon Tank w 80 lbs of Live rock that I set up Jan. 22nd. Had a diatom bloom in early february. Lost some fish early on and took the slow route since then. I added a CUC (Turbo, Nassarus, Tonga snails, some hermit crabs) and now have in addition to this a Long Tentacle Anemone, Black Urchin, Maroon Clownfish, Yellow Tang, Marine Beta and two Blood shrimp plus a cleaner shrimp. Three powerheads on a wave strip (Moving about 900 gph) plus the pump for my filter in the sump w two chemical filter bags of Chem Pure + Chem Pure elite (540gph). A Coralife needlewheel protein skimmer (Upto 125gallons) and two UV filters total of 35w. Started adding soft corals (Actually added 1) and a clam. Readings today Temp 78, pH 8.0, dK 4.5, Ca 450, Amm 0, Nitrite 0, Nitrate 0 SG 1.024


Question:
How should I deal w the low dKH and low pH with a normal (Or even high Calcium)? I have the two component Bionic, but last time I used it I think it did it incorrectly and killed some fish.

 

[melosu58]

Let`s figure out why the low PH. Do you have any type of glass cover over the tank? How often are you doing PWC`s? Read this

Low pH: Causes and Cures by Randy Holmes-Farley - Reefkeeping.com

 

[ronin33]

I have a glass cover. Up till this week had only done 1 partial water change. Tanks been running for 11 weeks (Used Cured LR and Biospira). Had yet to detect a spike in Nitrite, Nitrate or Ammonia. Was told not to do PWCs too often. Did a 10 gallon change yesterday.

 

[melosu58]

Was told not to do PWCs too often.

Whoever told you this was not giving good advice. Two main things that PWC`s do is 1) Replenish trace elements that are important for different processes that happen with your fish, corals and inverts. 2) Dilute excessive nutrients that promote poor water quality and fuel nuisance algea. As far as the glass top on your tank they promote low PH due to poor gas exchange at the surface. You will find out that your PH will go back to normal if you remove the glass top. JME

 

[ccCapt]

I agree with Mike on the water changes. Also, what brand salt are you using? I suspect testing error for your alk. That # seems way too low. I don't know of any salt that mixes to less than 7-8 dKH.

 

[melosu58]

As far as PWC`s read this

Water Changes in Reef Aquaria by Randy Holmes-Farley - Reefkeeping.com

 

[ronin33]

I have been using Coralife Marine salt. My tank has a sump. I added an air stone to the sump. Will this aid in gas exchange? OK, I did two 5 gallon water changes Monday and another Wed. Bought Seachem marine Buffer and had the two component Bionic Calcium Buffer system. Started doing partial water changes regardless of nitrate readings, Calcium has been consistently between 420-450. I have had the readings of my tests confirmed via my local LFS. Can assume that if this isn't a gas exchange problem, it is a build up in organic/inorganic acids? What is the difference in the Alkilinity component of the two part Bionic Buffer and the regular Seachem marine Buffer? How do you reach a happy medium between water changes, adding buffer and adding calcium? Seems like you could end up chasing your tail. Is it possible to dilute your Biofilter by performing partial water changes too often?

 

[jhampton_wsu]

I've never used the coraLife salt but according to a RC post it should be dkh 9.0 and Ca 560 mixed at 1.0264. at 1.024...
Reef Central Online Community - A General Guide to Salt Mixes
...your numbers should be slightly less than that. I would recommend a 10 percent water change every week or at least a 20 percent every two weeks. As posted above this will re-plenish your trace elements. Have you tested your newly mixed salt water? I always do this when I buy a new bucket of salt and sometimes in between. If your calcium is 420-450 I wouldn't dose it that is a good level. I would try to bring up my dkh no more than .5 dkh each day until it is back to normal and then see what happens with regular water changes. With one clam and one softie your tank shouldn't be using too much alk or Calcium. Also, unless there is major problem I wouldn't recommend doing a water change more than once every 3 days. IME the water needs time to stabalize.

Jason

 

[jhampton_wsu]

As far as PWC`s read this

Water Changes in Reef Aquaria by Randy Holmes-Farley - Reefkeeping.com

Good article.

Jason