High ph


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I'm really hating reef chemistry right now. I've been fine tuning Ca and alk for the last month. Only to find that now I have high ph. It tested high 2 weeks ago. Did a wc and this week it's still high. Read the reef chemistry provided by Herman in another post and also the associated ph problems article. Read the recommendations and trying to figure it out now. I know there are no easy answers and I just have to work it out slowly. Just po'd and frustrated and needed to vent. Here are my parameters in case someone has something helpful to add. Btw..I'm off my ass researching this now becaue I just bought two new fish and one didn't even make it through acclimation. lfs pointed to ph problem though I doubt if that's the major cause. It was a beautiful anthia too. I also realize that the problem may be my tests as well...can anyone rec a good ph test?

aga megaflow sump model 3
coralife skimmer
4x65w pcs
3 x 1200 1x 900 maxijets
dosing kent liq Ca & C-Balance 2 part
15-20g wc every other week

Ammonia 0
Nitrite 0
Nitrate 0
salinity 1.024
Ca 400
Alk 2.9 mil equivalents per liter
ph 8.5??*

*I use Red Sea tests. The chart has grey as 8.2, purple as 8.4 and royal purple as 8.6. My repeated tests come out as a navy color :)

2 ocellaris clowns
1 keyhole angel
3 chromis
1 yellow tailed damsel
1 sixline(new)
2 peppermint shrimp
1 serpent star
20ish hermits
20ish small snails
kenya tree


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pH 8.5, while high isn't extremely bad. In a non Ca reactor tank a pH of 8.4 is considered normal. You may need Mg in your system to buffer out the pH. It is extremely important to have a the right level to minimize pH swings. Epson salts is the best way to increase Mg levels.

More importantly is the pH swings, do you have big swings?


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FWIW, I use Chemi-pure which sparkles my water and keeps my pH at 8.2 all the time. Depending on your tank, it needs to be replace only every 4-6 months. I'm a firm believer in the leaving your tank alone and having as few additives as possible.
My motto: "The less you 'eff around with it, the less likely it'll 'eff up" :D


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Thanks for the quick replies. I would love to get to the point where I don't have to dose. But unfortunately even though we do wc regularly it doesn't seem to be keeping the numbers optimal. I always seem to be low Ca & Mg though alk seems to be ok. As for ph it seems like it's always 8.2-8.5 not sure if that's considered a big swing. I use IO salt. Is reef crystals a better choice? What other things should I be doing to promote a healthy tank that hopefully will eventually require less "tinkering"? I'm already feeding sparingly and the corals I keep don't even need high levels of Ca.
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Manhattan Reefs
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Howell, NJ
some would say oceanic is a good salt (high in calcium) i think masterswimmer (russ) uses that and only that he dont dose and his tank(s) are awesome...


Manhattan Reefs
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I defer to Solbby on these matters, but a pH swing of 8.2- 8.5 seems pretty optimal to me. I seriously doubt this is causing any problems for your system... if it creeps a bit higher perhaps... but I wouldn't drive yourself crazy if these numbers are accurate. Your LFS may be correct regarding your fish in the sense that THEIR pH may be really low and the jump to "normal" levels stressed your fish. It is always a good idea to find out what the water conditions are in the store i.e. pH and even more importantly, Salinity, as shops typically run a very low specific gravity to combat parasites Randy


Professional Commuter
Manhattan Reefs
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Wallingford, CT
According to Randy Holmes, a PH of 8.5 at peak is actually a good thing (as Martha would say).
.3 swing from low point to peak is not all that bad and unusual.
My reef tank has from day one peaked at 8.5 and at night can be in the range of 8.28 to 8.35.