Why is my tank consuming so little alk?

[JosephM]

I have a 29gal DT with 20gal sump. Mixed reef mostly LPS with some softies and SPS. I have 35+ frags in the tank. I started dosing ESV 2-part when I had around 10 corals and was dosing 13ml a day which is a little over .6dkh a day which was understandable with how few corals I had. Well once I started getting more I setup a doser, jebao DP-4. Got it all calibrated and such and set to 2ml 5 times a day. Ever since then I’ve been monitoring and my alk and it’s been slowly rising and I keep lowering my dosage. I was down to 6ml a day and it was still rising about .15 a day so I dropped to 5ml a day. Why in the world is it so low? Other parameters: salinity 1.0259 (tested a couple days ago), ph 8.2 (tested a month ago an hr after lights out), alk - 10.3 (tested tonight), calc - 455 (stable but tested a week ago), P04 - 0.05 (tested tonight), nitrates ~25ppm (tested a couple days ago), magnesium - 1575 (always been high since I started the tank but stable around there maybe slowly dropping)

Also noted - even though I bled the lines I see small air pockets in the lines which means it’s probably dosing even less then it’s set for)

 

[TheDragonsReef]

High nitrates and phosphates will slow growth of corals leading to less uptake of alk/cak/mag. I would aim for less than 10ppm nitrates and less than 0.1 phosphates

 

[JosephM]

High nitrates and phosphates will slow growth of corals leading to less uptake of alk/cak/mag. I would aim for less than 10ppm nitrates and less than 0.1 phosphates

Shoot my bad. It’s 0.05ppm P04, typo. But yeah totally working on getting the nitrates down with some chaeto. Can it cause that much of a difference?

 

[TheDragonsReef]

Shoot my bad. It’s 0.05ppm P04, typo. But yeah totally working on getting the nitrates down with some chaeto. Can it cause that much of a difference?

0.05 is fine for phosphates, 25 is ok for Nitrate but not preferred. I've never experienced any death due to nitrates around there but I see noticeably more growth at lower levels

 

[JosephM]

0.05 is fine for phosphates, 25 is ok for Nitrate but not preferred. I've never experienced any death due to nitrates around there but I see noticeably more growth at lower levels

Yeah. I try to stay around 5, 10 max on nitrates. I just got out of my battle with dinos and chaeto died around that time so they got out of control. I just got a big amount of chaeto today and I’ve been dosing MB7 to get them back in check