Alright need some help, I’ve never seen anything like this in my years of reefing. My tanks Alk is dropping like crazy all of the sudden. So the tank has been up and running for about 2 months I used live sand half dry rock from a 320 gallon and 120 gallon that have been running for a few years, the dry rock used was clean and mortared together with macro 400 reef cement. The tank has lps and softies and lots of fish that are well fed. I stopped testing daily a couple weeks ago as numbers were not moving much then I tested as normal a week later because a large colony of utter chaos was melting. The Alk had dropped to 4.9 dkh and calcium dropped to 390 ppm. I started upping my dosage to bring them both up over the last two weeks and just when it seem it’s moving it drops again today. I have no build up anywhere only 3 large rocks have coraline and for the last 4 days I’ve been dosing 100mls of Alk daily only to watch it keep falling. Tank is 180 gallons so this seems way too much. Calcium today was 435 ppm Mag 1450 Alk started the day at 5.9 and has dropped to 5.5 after dosing 100mls of Alk nitrates are 2ppm phosphate is 0 no nitrate or ammonia and salinity 1.025. Im stumped any help or thoughts would be awesome
Alk dropping like a stone
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Randy Holmes-Farley
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How many dKH per day is the alk consumption?
Dilan Patel
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how are you dosing. Make sure your lines are not clogged as well as do a manual test to make sure the dosing method is correctly working. I had a similar issue turned out my pumnp on my doser was messed up...easy fix that saved my livestock.
Randy Holmes-Farley
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How much in dKH? That’s the only way to know if the expected calcium drop is enough to measure or not.
Retro Reefer
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Thats a Lot going on in a 8 week old tank 
madweazl
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I'd double check the alkalinity results with another kit but at less than 1 dKh per day, you're not consuming all that much really (I dose 110ml/day of BRS 2-part in a 75g but I have quite a bit of growth going on).
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Randy Holmes-Farley
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Right. 1 dKH per day is on the low side, not dropping like a rock. Even a soft coral tank can use 2 dKH per day if there is coralline growth
