PH mystery... well to me.

[ocean.mirage]

I checked all my tank paramters.

DKh. 8
Calcium 460
salinity. 1.025
temp 79
ammonia o
nitrite next to zero
nitrate next to zero.
phos .2mg/L


So I have a 90G tank.

I had PH issues before. but i figured it out. I run my skimmer intake outside. I got a fresh air exchanger running in my house. I run a large fan over the water and I have air stones in the tank now. I also now run a tone of t5 sump lights at night.

So I usually dose 25ml of each part of B ionic every second day to keep PH, alk, and calc. up .

My tank was fluxing between 8.3 and 7.95 between night and day.

But now my tank is constantly falling to 7.85 every night.. for last week . even if I dose 30ml of each Bioinic part EACH day. This happened all of a sudden.

All I can think of.. as a cause...is
1. I added 4 new 2-3" fish in the last month.
2. I have progressive going from a 15% water change every week to a 15% change every two weeks now.
3. My Coral are growing a lot and very fast. and I have zoo's polyps eveywhere. and 12 lps and softies that are getting large in the tank.

what might be the cause of this sudden drastic need of alk dosing to keep the PH up?

Any thoughts?

is it safe to dose this much. and can I lighten up on the calcium because it is gettting high as I dose equal amounts to match the alk dosing.

[Untamed12]

I wouldn't worry about it. I think you are likely to cause more problems by trying to manipulate pH. Just focus your efforts on maintaining Alk and let the pH do what it does naturally.

[Peter Eichler]

Increased demand for corals and increased coraline and halimeda growth will do that. 30ml each day is nothing, if I used B-Ionic for my system (about 135 total gallons) I'd have to dose over 500ml a day.

[ocean.mirage]

Wow....really? so what do you do to dose instead...cause 500ml's a day would be expensive!

[Peter Eichler]

<a href=showthread.php?s=&postid=13158890#post13158890 target=_blank>Originally posted</a> by ocean.mirage
Wow....really? so what do you do to dose instead...cause 500ml's a day would be expensive!

For a while I was making my own 2 part. Now I use a calcium recator.

[crvz]

How are you testing for pH? I assume a probe, but if it's a test kit I wouldnt trust the numbers at all (nor would I really test a probe unless it's been calibrated recently).

But as untamed pointed out, I wouldnt worry about it if there arent other problems. Mine always hits 7.8 right before the lights come on, and it's never been an issue.

[reverendmaynard]

You said you have "T5 sump lights". What are they lighting and how much of it?

[LOTUS50GOD]

Your PH is in the ballpark. I wouldnt worry. If you want to raise it bump your DKH to about 10 and your PH will go up.

If you dosed kalkwasser at night that would help stablize your PH as well

[ocean.mirage]

I have a 20G sump with 8g Refugium. I keep 2- 2' 10,000k and 1-2' actnic t5 on above it.

[aquaman67]

Unless you are using a recently calibrated meter that has a accuracy of +/- 0.01 be careful about chasing numbers. You can do more harm than good.....

[ocean.mirage]

well I calibrated it 6 months ago. how often should you calibrate them?

[aquaman67]

I would calibrate mine every other week or once a month at a minimum if you are going to make changes based on it's readings.

Here's a good article on the subject....

http://www.advancedaquarist.com/issues/feb2004/chem.htm