Alkalinity help!!

[Joel Franco]

I have a Deep Blue 80 gallon tank that has been up since the 24th of December. Everything from a 75 gallon that was moved over into the new tank with little losses. SPS mainly. Everything has been fine until the end of last weekend when I noticed that the tank was consuming calcium but not alkalinity. Slowly this entire week the alk was been increasing on its on without dosing 2 part. I am using Fritz salt and I get about 8.3dkh out of the mix. The corals and fish seem to being doing really well but the alk just keeps climbing. Since I lost a lot of SPS i mainly have LPS, zoas and some SPS. I know your going to ask so here is my parameters. I check every evening at the same time.
Current as of this evening:
Temp: 78 degrees - Apex
PH: 7.93 - Apex
Calcium: 435 ppm - Salifert
Alk: 8.9dkh- Salifert
No3: 10ppm - Salifert
Po4: 0.1ppm - Salifert
Mag:1460 ppm - Red Sea Pro
Salinity: 1.026
What could be causing ALK to increase?

 

[Diesel]

Mmmm weird.
Did you double check on the PH?
What do you use to dose and how?

 

[Joel Franco]

I have not double checked the Ph but will now that you mentioned it. I dose Oceans Blend part 1 and 2.

 

[GoVols]

Mmmm weird.
Did you double check on the PH?
What do you use to dose and how?

Bump

 

[Joel Franco]

I tested the PH and got 7.8 using a Red Sea test kit.

 

[Diesel]

I have not double checked the Ph but will now that you mentioned it. I dose Oceans Blend part 1 and 2.

Never heard about or seen this Ocean Blend

http://www.oceansblend.com/2_part.html

Maybe @Randy Holmes-Farley has some inside on this or lets get the #reefsquad on this thread as well.

 

[GoVols]

I have not double checked the Ph but will now that you mentioned it. I dose Oceans Blend part 1 and 2.

I never heard of th

I tested the PH and got 7.8 using a Red Sea test kit.

Was it the Red Sea Pro kit?

 

[GoVols]

Never heard about or seen this Ocean Blend

http://www.oceansblend.com/2_part.html

Maybe @Randy Holmes-Farley has some inside on this or lets get the #reefsquad on this thread as well.

Same here.

 

[Joel Franco]

Its a really good product. I would recommend it. I have never had any issues with it.

 

[GoVols]

Tagging along :)

 

[Joel Franco]

I started Sunday-Tuesday at 8.4 alk and the past two days it has been climbing .2 to .3 dkh. I am sitting at 8.9 now.

 

[saltyfilmfolks]

How low is your PH dropping at night?

 

[Joel Franco]

My PH drops to a max of 7.6 at night.

 

[redfishbluefish]

How are you measuring salinity? The number you provided above in the OP, when was that tested....and was it on DT water. Here's my thinking......you're using saltwater in an ATO and it not only is raising alkalinity, but would also be noted in a rise in salinity.

Otherwise I'm scratching my head on this one, but I'll be following.

 

[GoVols]

My PH drops to a max of 7.6 at night.

Have you been dosing anything like PH buffer? It will raise your Alk.

 

[Joel Franco]

I used a refractometer that I calibrated again after I noticed the rise of alk. I am using RO water that was freshly made 2 days ago. If I was putting in saltwater water with the ATO the calcium would also be increasing but it is not. I only dose part 1 as needed to keep calcium stable.

 

[Joel Franco]

Also, I have not dosed anything in the tank for the past two days. Where is Randy when you need him?

 

[redfishbluefish]

I used a refractometer that I calibrated again after I noticed the rise of alk. I am using RO water that was freshly made 2 days ago. If I was putting in saltwater water with the ATO the calcium would also be increasing but it is not. I only dose part 1 as needed to keep calcium stable.

This remains a head scratcher for me....because it's always alkalinity that drops quickly, not calcium. I've got to sleep on this one and give it more thought. What's the expiration on the test kits? My experience with outdated calcium and magnesium kits....they'll give you low numbers.

 

[jsker]

Are you dosing anything else besides the 2 part?

 

[Joel Franco]

They are brand new test kits. Purchased last Friday. I check my parameters and write them down in a journal everyday.