Alkalinity ok or to low at 7.9?

HAWKBOYS · 07/13/2018, 02:42 PM

Current Tank Reads:
Alkalinity 7.9
Magnesium 1400+
PH 8.1-8.3
Temp 77
Nitrites, Nitrates, Ammonia - 0
Phosphate .025

Not currently dosing, just water changes, thinking about adding KALKWASSER to ATO in future, but am unsure since the Alkalinity is 7.9?

Thanks

HAWKBOYS · 07/13/2018, 02:45 PM

Sorry, calcium levels have stayed between 450 - 480

mattgumaer · 07/13/2018, 02:53 PM

Seems fine to me. Some people like to run higher to try to maximize sps growth but, personally, I've never really seen adverse effects from low alk, when the alk has been above 7.

Consistency may be as important as the absolute number. If you do water changes every week and your starting alk is 13 and then drops to 7.9 over the week, that's a pretty big swing, even if neither number is inherently bad.

I'd take frequent readings over a water change interval and see where it starts and where it ends before replenishing via water change. If the swing is 'big', you may want to dose kalk. 'Big' likely depends on the coral you're keeping. Some are far more sensitive than others to alk changes.

Some insight into your coral types/density may help people respond but, if you're alk is only dropping to 7.9 over a water change interval without dosing, that strong suggests that you don't have a lot of alk consumption happening in your tank.

Matt

Sk8r · 07/13/2018, 03:16 PM

Ditto. 7.9-9.0 is a good range.

Uncle99 · 07/13/2018, 07:47 PM

Alk fine, numbers good, except Nitrate, if actually zero, corals will starve.
Try 2-5ppm nitrate....as a suggestion...

bertoni · 07/13/2018, 11:54 PM

A lot of Tanks of the Month have run at pH 7.8. It's a fairly common level for a tank in a house.

josephxsxn · 07/14/2018, 11:59 AM

I run my tank around 7.5 DKH just fine but dose for stability to avoid swings.

07/13/2018, 02:42 PM	#1
HAWKBOYS Registered Member Join Date: Aug 2007 Location: stillwater ok Posts: 5	Alkalinity ok or to low at 7.9? Current Tank Reads: Alkalinity 7.9 Magnesium 1400+ PH 8.1-8.3 Temp 77 Nitrites, Nitrates, Ammonia - 0 Phosphate .025 Not currently dosing, just water changes, thinking about adding KALKWASSER to ATO in future, but am unsure since the Alkalinity is 7.9? Thanks

07/13/2018, 03:16 PM	#4
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	Ditto. 7.9-9.0 is a good range. __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

07/13/2018, 11:54 PM	#6
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	A lot of Tanks of the Month have run at pH 7.8. It's a fairly common level for a tank in a house. __________________ Jonathan Bertoni

07/13/2018, 02:45 PM	#2
HAWKBOYS Registered Member Join Date: Aug 2007 Location: stillwater ok Posts: 5	Sorry, calcium levels have stayed between 450 - 480

07/13/2018, 02:53 PM	#3
mattgumaer Registered Member Join Date: Jun 2013 Posts: 561	Seems fine to me. Some people like to run higher to try to maximize sps growth but, personally, I've never really seen adverse effects from low alk, when the alk has been above 7. Consistency may be as important as the absolute number. If you do water changes every week and your starting alk is 13 and then drops to 7.9 over the week, that's a pretty big swing, even if neither number is inherently bad. I'd take frequent readings over a water change interval and see where it starts and where it ends before replenishing via water change. If the swing is 'big', you may want to dose kalk. 'Big' likely depends on the coral you're keeping. Some are far more sensitive than others to alk changes. Some insight into your coral types/density may help people respond but, if you're alk is only dropping to 7.9 over a water change interval without dosing, that strong suggests that you don't have a lot of alk consumption happening in your tank. Matt

07/13/2018, 07:47 PM	#5
Uncle99 Crab Free Zone Join Date: Sep 2017 Location: Ontario, Canada Posts: 2,906	Alk fine, numbers good, except Nitrate, if actually zero, corals will starve. Try 2-5ppm nitrate....as a suggestion...

07/14/2018, 11:59 AM	#7
josephxsxn Registered Member Join Date: Oct 2017 Location: DTW, Michigan Posts: 122	I run my tank around 7.5 DKH just fine but dose for stability to avoid swings.