SPS and pH

[IndyReefMan]

I need some assistance from some of you more seasoned SPS keepers. I have difficulty keeping SPS frags, especially Montipora. They're okay for a few weeks and then they bleach and/or STN. I've never had any problems with LPS. The tank is two years old and I've been trying to keep SPS for about 8-9 months. I have checked thoroughly with a magnifying lens and don't see any red bugs, nudi's or other predators anywhere. I was calibrating the pH controller on my calcium reactor the other day and when I was done I stuck it in the sump out of curiousity and it read 7.9 (lights out). I checked it later after the lights were on and it read 8.0 I was very surprized since my Salifert colorimetric test always showed 8.0-8.2 or so. I know the reactor is driving the pH lower so my question is: Is this low pH the reason I'm having difficulty with SPS. The rest of my tank parameters are as follows:

Ammoniia=0
Nitrite=0
Nitrate=1ppm (Salifert)
Phosphate= Undetectable (Salifert)
Calcium=420
Alkalinity=8.5 dKH
Magnesium=1290
Specific Gravity=1.025
Temp=79
ORP=430 (no ozone)
pH=7.9 (Lights out)/ 8.0 (Lights on)

I have purchased a pH monitor so that I can more accurately track this now. I have also ordered some Kalkwasser to try to raise the pH slowly and see if that helps. Do you think this pH range is what is giving me problems?

[seminolecpa]

I think there may be some other issue, my PH is that low and both my acros and montis are doing fine and have been for some time.

[TCU Reefer]

My pH is similar to yours. There must be other issues as mentioned above.

I think the main thing with pH is consistency and stability, just like any other parameter. As long as it's not constantly fluctuating, it shouldn't be an issue.

[Big Boy69]

I was told by Todd from Something Fishy not to worry what the PH says, just make sure your DKH and meq/ml is correct and let the PH do what it's going to do.

[Lpabsolute]

I agree with the above answer from "TCU Reefer", there must be another issue besides the pH. As long as your pH is not constantly changing, then i don't see it being that big of an issue. Wish i could offer more in terms of a defenative answer, but....Good Luck in the future with trying to keep these corals...

[GMAX]

You dont mention the flow you have in your tank. SPS like lots and lots of it. Preferable random and chaotic. Since your profile say you are a long time freshwater hobbyist, this can be a major change. You want to turn your tank over like 30 to 50 times. Some would say a lot more. Requires more than a return pump. Lots of powerheads, and preferable difuse distribution from the powerhead like a Tunze stream pump ( or three ).

[Serioussnaps]

usually it is not a set parameter that causes problems....its the swings in those params...

if you say your ph is 8.0 fine...kind of low for my liking but its fine.....now if you say your ph is 7.8 at night and 8.25 during the day we have a problem...get my drift???

you should try to keep ALK rock solid at a set paramater...i go for 8-9 in there somewhere but try to keep it on that number 24/7/365

look into dripping kalk to help stabilize your params...i bet there are swings going on you arent noticing....oh you are now dosing kalk...good decision...i started typing before i read the whole post!

also....good move on ph monitor...no nice sps system should be without one...

i think this will really help...


test your ALK at the same time every day after a WC for about 4-5 days and watch for swings...i bet this will solve your problem


also...what is your daily temp swing...do you have a temp controller? temp swings can cause this too


and the final suspect--->>>> what is your acclimation procedure in terms of acclimating to the lighting!!!!

[Serioussnaps]

Whats your flow??? flow could be an issue or contributor to other problems

[IndyReefMan]

My flow is--

1) One Mag 5 as return pump (should be approx 300gph at 4' head height).
2) Four Maxijet 1200's on wavemaker (295gph each).
3) One maxijet 400 always on and hooked-up to UPS in case of power loss.

Temp doesn't swing much and I monitor it closely. Temp= 78.5-79.5 degrees. Two 4" canopy fans and one large 20" fan blowing across the sump. The system is located in a basement which also helps with temp stability... it rarely gets above 70 degrees in the basement.

As my first posting suggests, all parameters are in the acceptable range. The pH was the only thing that seemed askew. I have checked it often over the past couple days and I haven't seen it lower than 7.9 or higher that 8.05.

[IndyReefMan]

Light acclimation procedure is--

1) After changing bulbs, I place four "window type" screens over the top of the display. Then, I remove one screen every five days. This seems to work pretty well.

2) Upon introducing a new specimen, I place it at the bottom of the tank in a position so that it is not diectly under MH bulbs. Then, one week later I move it laterally so that it is still on the bottom but directly under where I plan on postioning it. Then one week later, I slowly move it up to it's final position. Generally, I place acros in the top third of the tank and montiporas in the middle (some closer to the bottom).

[DrBDC]

Nothing wrong with the pH other than excess CO2. Be it from running a ca reactor or just from inside conditions. You can very easily bump it a little with the kalk but rememer to tune down the ca reactor just a little because some of your ca and alk will be coming from the kalk. i.e. watch your levels. You may be able to boost it a little w/o just from more ventillation such as opening the windows more often or running a line outside for your skimmer needs.

Your ORP is def. not 430 w/o ozone. Soak the probe in vinegar for about 30-45 minutes and use a toothbrush to make sure that it is good and clean. You'll probably need to repeat that every 1-2 weeks. After you clean it, the reading will be correct w/in 12-24 hours or even sooner. You'll know it's time to clean it when it hits 330-360.

[IndyReefMan]

I was surprized to see an ORP reading that high too. The monitor is only three weeks old and I have soaked the probe in vinegar once already. ORP readings before and after I cleaned it show natural ORP readings of 430. The only time I see it go under 400 is after I perform a water change. Within 48 hours of the water change, ORP is back above 400. It is a Pinpoint monitor and the instructions say that it does not require calibration or adjustment. I guess that it could be a faulty probe. Has anyone else seen natural ORP readings above 400?