ALK stopped dropping STN

stevenVDB

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5 weeks ago my skimmer overflowed during the day, I’m guessing 4-5 hours.

The day after some corals had signs of RTN, lucky the corals didn’t die and RTN stopped.
Last week I introduced some some corals and all of a sudden there was no ALK consumption anymore.

The corals that were impacted by previous RTN decided to STN and are in a stage of completely dying

Tank is 8 months old 425 L
Alk 8.5
Ca 480
MG 1320
Po4 0.05
NO3 16-20
Sal 35
Temp 25.5

LEDs reefted 115 running at 67%
Added last week some AI blades as well running at 15% wanted to build it up slowly
 
5 weeks ago my skimmer overflowed during the day, I’m guessing 4-5 hours.

The day after some corals had signs of RTN, lucky the corals didn’t die and RTN stopped.
Last week I introduced some some corals and all of a sudden there was no ALK consumption anymore.

The corals that were impacted by previous RTN decided to STN and are in a stage of completely dying

Tank is 8 months old 425 L
Alk 8.5
Ca 480
MG 1320
Po4 0.05
NO3 16-20
Sal 35
Temp 25.5

LEDs reefted 115 running at 67%
Added last week some AI blades as well running at 15% wanted to build it up slowly
I'm sure others will chime in, but it probably wasn't a great idea to add anything new until you saw more positive recovery like new growth or repair) before adding anything new.

What did you add?

If it were me I'd probably do a water cghange just beasuse. I might ior might not run carbon. If I did it would be a small amount you don't want to strip anything out too fast.

Most importantly I'd be testing Alk and lot. Make sure you trust the kit (in fact I would have 2 different brands and make sure your not getting false readings) before you change anything. If your certain the corals have decreased the consumption and Alk is on the rise I would decrease the dosing. The last thing you want is instability again in the form of rising Alk.

I've had issues where I saw Alk rising and I'd regular skip doses just to try and keep Alk flat.

Good luck, mostly it's a wait and see thing but I would want to make sure my Alk didn't continue to climb from it's typical baseline (even if that meant stopping my dosing).
 
I thought I would be good after 5 weeks but seems I didn’t, again learned that even 5 weeks is rushing in this hobby

Im testing alk with trident and every 2 weeks with hanna

I added a 1 Monty plate, 1 green slimmer, 1 acro plate and 1 torch.

I do weekly 10% water changes,

Forgot to say that My alk used to be at 8.3. When I saw it raising I stopped dosing. So it went from 8.3 to 8.5 in a day last week

I also run carbon pellets in a reactor. Small amount. Would it be better to stop carbon
 
Last edited:
Sorry you are having issue's but I'm not sure exactly what your question is, you seem to be working through it. But if your alk is increasing then i would cut the dosing until the corals rebound and start growing again.
 
Sorry you are having issue's but I'm not sure exactly what your question is, you seem to be working through it. But if your alk is increasing then i would cut the dosing until the corals rebound and start growing
I’m having STN starting from the tips after my tank stopped consuming alk
 
I’m having STN starting from the tips after my tank stopped consuming alk

Is it possible the STN is the cause of the drop in consumption not the result? I can't help with the STN itself because it still a mystery to me why it happens.
PS I don't think rising from 8.3 to 8.5 is going to cause a problem.
 
Is it possible the STN is the cause of the drop in consumption not the result? I can't help with the STN itself because it still a mystery to me why it happens.
PS I don't think rising from 8.3 to 8.5 is going to cause a problem.
I’m really confused on what the alk is currently doing. It’s a rollercoaster. Today in 3h it jumped from 8.4 to 8.58



IMG_2081.png
 
Nice, when did you start to introduce sps to your system
That tank is a few months old but it's a move from a tank I started to try SPS. I don't remember exactly but I added a bunch of frags pretty soon after starting, maybe a month. The sump was full of old live rock which I always use. I think it helps things stabilize sooner and I can pretty much avoid the uglies..

The LPS are from another tank. The frags are mostly from battle corals.
markup_1000014166.jpg


3 years later just before I moved out of the tank.
PXL_20260510_171216765.MP~3.jpg



PS. The first year was tough with some losses. Things settled down after that and I'm able to keep it pretty stable just dosing AFR for alk and calcium along with ammonium and sodium phosphate because the tank runs chronically low N and P.
 

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