Will A few Frags Lower Alk by that much?

jeffww · Sep 17, 2019

I have a stylo (3"), birdsnest (2"), M. spongodes (3" circle), stunner (4" diameter) and tenuis (1.5") in my small 7g tank. Everyone is doing well. I use IO reef crystals and it comes out to be 8.5dkH when fresh. I haven't been consistently checking kH because I figured frags can't be using that much kH. This weekend I added more acropora and did a kH test before the weekly water change it was about 7? Does this amount of kH drop seem normal? I suppose in a smaller tank there is less calcium by mass so maybe that is why a little growth can swing alkalinity a lot? In this case, should I start dosing 2part?

Jake_the_reefer · Sep 17, 2019

jeffww said:
I have a stylo (3"), birdsnest (2"), M. spongodes (3" circle), stunner (4" diameter) and tenuis (1.5") in my small 7g tank. Everyone is doing well. I use IO reef crystals and it comes out to be 8.5dkH when fresh. I haven't been consistently checking kH because I figured frags can't be using that much kH. This weekend I added more acropora and did a kH test before the weekly water change it was about 7? Does this amount of kH drop seem normal? I suppose in a smaller tank there is less calcium by mass so maybe that is why a little growth can swing alkalinity a lot? In this case, should I start dosing 2part?

You will be suprised. I've been running thinking "they are all frags they cant use that much alk" but in my 20g a handfull of frags are using a ton of alkalinity so I have to start dosing because water changes arent cutting it anymore. I dont have any big colonies just yet but wow the alk consumption.

jeffww · Sep 17, 2019

I guess it's time to turn on the other two heads of my dosing pump. Hopefully means I will see some faster growth.

brawthy · Sep 17, 2019

7 gallons of volume is an extremely small amount of volume. Your parameters will fluctuate greatly unless you are dosing

Purplelobst92 · Sep 17, 2019

Time to start dosing and testing like a maniac until you learn the tanks consumption rate, start a journal, I keep one to keep track of my tanks parameters.

jeffww · Sep 18, 2019

Yes. It looks like just today I used ~0.3 dkH in alk. Also checked my nutrients and they are at 0.02 phos and <1ppm nitrate. So in addition to dosing 2part I've started to spike my top off water with some phosphate and nitrate salts. I had just beaten dinos by raising phos to 0.2 and nitrate to 10ppm and have been doing just 20% W/Cs weekly since then. I'm really surprised I am nearly bottomed out again in 2 weeks since last dosing.