Question about alkalinity

Mr31415 · 08/09/2006, 02:06 PM

If my pH varies between 8.20 and 8.40 every day (low end is at sun rise and high value is when lights go off) - but never go outside these bounds, and my Calcium levels stay above 440mg/l, do I need to be concerned if my alkalinity is at 6-7dKH?

Even if I want to keep LPS or SPS?

reefnetworth · 08/09/2006, 02:15 PM

ALK is low, should be around 7-12 dKH. pH is high, as long as it doesnt get higher than 8.4 you might be OK. acceptable pH is 7.8-8.4 as is found in the oceans. C02 will lower the level, but i would use sodium carbonate (baking soda) to lower pH if needed. i dont encourage it unless it gets higher than 8.4. mixing at 1 1/4 cups per gallon of water then dose at 1mL per gallon. or white distilled vinegar will also temp. lower pH by 0.3ppt if you add 1 mL per gallon of tank water in a high flow area, such as the sump. never allow either to hit corals direct. REEF-ON!

mg426 · 08/09/2006, 02:38 PM

What are you measuring your Ph with? Test kits are kind of hard to read. If its a monitor and you are sure of your reading then your Ph is OK. (Its on the high end) To address your alk it could stand to come up a bit. What are you using to maintain your alk?? Boosting your alk may push your PH even higher, so I would go slowly and keep a close eye on things. 8.5 is as High as you want to go with your PH

Mr31415 · 08/09/2006, 02:43 PM

Thanks. But my question was whether an Alkalinit of 6-7dKH and the other params as I mentioned them, would be sufficient to keep a healthy reef? I have tried every means on earth apart from a complete system water change to correct my low alkalinity - nothink works for longer than a couple of days.

Mr31415 · 08/09/2006, 02:45 PM

pH is measured with a $1200 electronic AquaTronica controller. It is accurate - I ensured I calibrated it correctly.

I tried dosing baking soda and it brings alk up to 8dKH, but then pH tends to go over 8.5. Obviously I am looking for a balanced supplement, so when pH was at 8.5, Calc. at 450mg/l and alk. at 8dKH I started dosing kalkwasser to my topoff RO water. It then plummets to alk. 6 in a couple of days.

bertoni · 08/09/2006, 03:23 PM

Lower alkalinity might cause problems for corals as they try to deposit their skeletons. If the tank has no corals and coralline algae isn't desired, then alkalinity isn't as important. This article discusses calcification:

http://www.advancedaquarist.com/issues/apr2002/chem.htm

bertoni · 08/09/2006, 03:24 PM

http://www.reefkeeping.com/issues/2005-03/rhf/index.php

Oops, that article discusses high pH problems.

Mr31415 · 08/09/2006, 03:33 PM

bertoni - thanks for that first link. It is what I was looking for. Seems I am in for a massive water change - I think I have an ionic imbalance. 550l of RO water at 80l per 24 hours, it will take a while.....

rigleautomotive · 08/09/2006, 03:33 PM

i think you can safely raise alk with ESV 2 part cal buffering system but if your animals look healthy and growth is acceptable to you your parameters are ok. just not optimal

08/09/2006, 02:06 PM	#1
Mr31415 Registered Member Join Date: Jun 2006 Location: Surrey, Canada Posts: 1,926	Question about alkalinity If my pH varies between 8.20 and 8.40 every day (low end is at sun rise and high value is when lights go off) - but never go outside these bounds, and my Calcium levels stay above 440mg/l, do I need to be concerned if my alkalinity is at 6-7dKH? Even if I want to keep LPS or SPS?

08/09/2006, 02:15 PM	#2
reefnetworth Premium Member Join Date: Mar 2006 Location: U.S.A. Posts: 3,810	ALK is low, should be around 7-12 dKH. pH is high, as long as it doesnt get higher than 8.4 you might be OK. acceptable pH is 7.8-8.4 as is found in the oceans. C02 will lower the level, but i would use sodium carbonate (baking soda) to lower pH if needed. i dont encourage it unless it gets higher than 8.4. mixing at 1 1/4 cups per gallon of water then dose at 1mL per gallon. or white distilled vinegar will also temp. lower pH by 0.3ppt if you add 1 mL per gallon of tank water in a high flow area, such as the sump. never allow either to hit corals direct. REEF-ON! __________________ GIVE A MAN A FISH, YOU FEED HIM FOR A DAY. TEACH A MAN TO FISH, HE FEEDS HIMSELF FOR LIFE. (NEVER, underestimate another man's greed) Current Tank Info: SPS dominated barebottom display with BB sump since 2005, most consistant parameters in 19+ years of reefkeeping.

08/09/2006, 02:38 PM	#3
mg426 Registered Member Join Date: Jan 2006 Location: maryland Posts: 6,923	What are you measuring your Ph with? Test kits are kind of hard to read. If its a monitor and you are sure of your reading then your Ph is OK. (Its on the high end) To address your alk it could stand to come up a bit. What are you using to maintain your alk?? Boosting your alk may push your PH even higher, so I would go slowly and keep a close eye on things. 8.5 is as High as you want to go with your PH __________________ I found a way to make a small fortune running a reef tank. Start with a large fortune. Unofficial President of the SEACLONE haters club Current Tank Info: 125 mixed reef 110 lbs LR, 1x250watt XM 20K MH 2x175watt XM 20K MH on Magetics 2X96 watt actinic PC, 220 watt VHO actinic, 30 gallon refugium, closed loop system powered by Sequence Dart MSX 200 skimmer 38 gallon sump, Oceansmotions squirt

08/09/2006, 03:23 PM	#6
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	Lower alkalinity might cause problems for corals as they try to deposit their skeletons. If the tank has no corals and coralline algae isn't desired, then alkalinity isn't as important. This article discusses calcification: http://www.advancedaquarist.com/issues/apr2002/chem.htm __________________ Jonathan Bertoni

08/09/2006, 03:24 PM	#7
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	http://www.reefkeeping.com/issues/2005-03/rhf/index.php Oops, that article discusses high pH problems. __________________ Jonathan Bertoni

08/09/2006, 02:43 PM	#4
Mr31415 Registered Member Join Date: Jun 2006 Location: Surrey, Canada Posts: 1,926	Thanks. But my question was whether an Alkalinit of 6-7dKH and the other params as I mentioned them, would be sufficient to keep a healthy reef? I have tried every means on earth apart from a complete system water change to correct my low alkalinity - nothink works for longer than a couple of days.

08/09/2006, 02:45 PM	#5
Mr31415 Registered Member Join Date: Jun 2006 Location: Surrey, Canada Posts: 1,926	pH is measured with a $1200 electronic AquaTronica controller. It is accurate - I ensured I calibrated it correctly. I tried dosing baking soda and it brings alk up to 8dKH, but then pH tends to go over 8.5. Obviously I am looking for a balanced supplement, so when pH was at 8.5, Calc. at 450mg/l and alk. at 8dKH I started dosing kalkwasser to my topoff RO water. It then plummets to alk. 6 in a couple of days.

08/09/2006, 03:33 PM	#8
Mr31415 Registered Member Join Date: Jun 2006 Location: Surrey, Canada Posts: 1,926	bertoni - thanks for that first link. It is what I was looking for. Seems I am in for a massive water change - I think I have an ionic imbalance. 550l of RO water at 80l per 24 hours, it will take a while.....

08/09/2006, 03:33 PM	#9
rigleautomotive Premium Member Join Date: Sep 2004 Location: Northeast Pennsylvania Posts: 3,705	i think you can safely raise alk with ESV 2 part cal buffering system but if your animals look healthy and growth is acceptable to you your parameters are ok. just not optimal __________________ Dan Rigle President, * Reef Conservation Society TOTM December 2010 Coral Magazine Sept/Oct 2012 Current Tank Info: 180 gal SPS dominated display, 3 X 250 watt Radiums , lumenarc III minis , with VHO actinics, ETS downdraft skimmers, closed loops and 2 Tunze 6105 & 7095 controller,DIY calcium reactors DIY custom built sumps,since 1992