Please Help me out here.. Ph,alk I'm a bit lost here

[Jakef150]

My cocnern is ph drops way down to 7.4 at night.

I even have sodalime scrubber small 8oz in a 12oz Gatorade bottle( I might put more sodalime in it), window opens and nothings work!!

I uses to have good # of ph range 7.8-8.1 then sudden dropping into 7.4-7.8?

I have pinpoint PH and did a re check Cali. 7.00 and 10.00 also API test ph is pretty close what ph monitor reads.

There is nothing change at all around my home. I do not dose any thing but alk by BRS recipe 1.

I set a brs doser 12ml recipe 1 alk at night 330am 3x a week. ALK always stay at most 7-8 but Ph isn't.

Should I set Monday-Friday at night to dosing recipe-1 alk 1-1.5ml every night instead of 3x a week to keep ph up? ?

So far SPS are doing good, and I have noticed 2/3 zoa melting and other Lps are doing good.

My tank info:

Biocube 29 *open top*, AI SOL blue, tunze 9002 skimmer hooked to sodalime bottle , BRS gfo, rox carbon, few marcoagle trees, ato 5 gal, using rodi system with tds -0, sodalime scrubber .

Change water every weekend 5 gal w /ESV salt

1025
78.5*
440 cal
Alk 7-8.5
Nit/ nit-0
Phos 0.00-0.03 Hanna checker
Mg 1440 salifert test
PH 8.4 at night 7.4 and daytime 8.0


ADVICE ??

Thanks
Jake

 

[Randy Holmes-Farley]

A swing from 8.4 to 7.4 sounds like it may be testing error due to electrical interference. The Pinpoint is known for this. Is it on battery or AC (AC is more prone to interference with the Pinpoint).

When you read 7.4 in the tank, try taking the meter and a cup of tank water into another part of the house and see what you get. Maybe try the same at the daytime peak.

 

[Jakef150]

Ok will do that tomorrow am and report back

Pinpoint ph AC plugged into surge, not battery

Thanks
Jake

 

[Randy Holmes-Farley]

Trying the battery might also be a good test then.

 

[Jakef150]

Ok, I set doser 1ml alk mon-fri.

This am I tested at 9am , result 9 alk and ph is at 7.6, and API test read 7.8 match color chart.


I used a cup of sw and took out pinpoint to bathroom and it's almost same , read at 7.62-.63

Thanks
Jake


Ok very interested, friend of mine dropped by for shorty time to help me out and we tested alk by salifert and result was surprised, it's 7.4 !!

 

[Randy Holmes-Farley]

pH 7.6 is about the bottom that folks realistically see. Below that and I begin to more strongly suspect errors. Coral skeletons, live rock, and sand will slowly dissolve below that.

 

[Jakef150]

I blamed API test that got error read At high (9alk) cuz after tested alk with salifert it reads at 7.2 then re tested 7.4 and that why ph way is low.

So, I dosed 9ml of recipe 1 alk, it raised to 8.3 ( salifert tested) and ph is now at 7.9.

I do not see any foul in my tank...SPS, other are do fine.

Thanks
Jake

 

[Jakef150]

Used a cup of SW from my tank to outdoor for 2.5 hrs...it's 7.7 ph so that's off..

I called pinpoint co..they said to follow the table by 7.00 and 10.00 Calibration fluid on side "temperature correction table"

So I checked the fluid temp inside bag and it's 68* so I re calibration again...and in my tank now reading at 7.88 and is slowly increase # of ph.

Thanks

 

[Randy Holmes-Farley]

OK, 7.88 seems fine. Where in the light cycle was that?

 

[Jakef150]

Light on at 1130am as morning light then strong light at 12pm and off at 930pm