Should I raise my alkalinity ?

[Idech]

My tank is 75 gallons and 11 months old. It has about 20 corals, soft and LPS. Most are having a hard time, skeletons are showing and some polyps even leave the frags.

I’ve had a hard time with stability for about 6 months because of a faulty mag test. I kept dosing magnesium when I didn’t need to. When I realized it, my levels were at 1640 ppm or so. Since then I’ve been slowly decreasing mag levels.

I’ve also had moderate dinos for about 5 months. They have gone away 3-4 weeks ago after dosing silicate for 4-6 weeks, a 3 day blackout, dosing Microbacter 7, phyto and raising nitrates and phosphates that had bottomed out.

Now it seems my alkalinity is going down a little bit. I use Red Sea blue bucket and alkalinity at 35 ppt is 7.8 to 8.2. My alkalinity is 7.6 and salinity is about 1.0256.

I want to avoid another event that will further damage the corals. Should I raise my alkalinity a little bit ? To 8.4 ppm maybe ?

Here are my current parameters :
alk : 7.6
mag : 1520
cal : 445 ppm
nitrates : 12 ppm
phosphates : close to 0


Thank you !

 

[fishski13]

I would work on raising your alkalinity slowly and monitor it. I usually like to keep alkalinity between 8 and 9.

But I would say as your described your corals not looking to good, I would focus more on stability. Corals need better satiability to allow for healthy and growing polyps. I would say this is your biggest goal right now to get you back on the right track.

 

[Idech]

I would work on raising your alkalinity slowly and monitor it. I usually like to keep alkalinity between 8 and 9.

But I would say as your described your corals not looking to good, I would focus more on stability. Corals need better satiability to allow for healthy and growing polyps. I would say this is your biggest goal right now to get you back on the right track.

I understand that but not sure what more I can do. I’m doing one small WC per week to lower magnesium. It lowers it by 40 ppm.

I’m not doing anything else that would alter stability. There must be something I’m missing.

 

[shakacuz]

what do you use to test?

 

[Idech]

what do you use to test?

Nitrate : Hanna
Phosphate : Salifert or Aquaforest (my Hanna reagents are probably bad so I can’t use this checker for now)
Mag, cal and alk : Red Sea
PH : API
Salinity : instant ocean hydrometer

 

[Falc!]

I run alk at 7.3-7.5 and overall parameters as close to natural sea water

 

[miyags]

Look at what Fragbox corals keep their Mag at..They keep it higher, to avoid coral flesh damage

 

[Randy Holmes-Farley Verified Community Expert]

The alk seems fine to me unless the primary goal is fastest hard coral growth.

 

[Idech]

The alk seems fine to me unless the primary goal is fastest hard coral growth.

That’s good to hear. My goal is to have corals that actually survive.

So low alkalinity isn’t what is causing the corals to leave their skeleton. I’ll leave it alone then, I have enough trouble with the whole thing as it is.

 

[Randy Holmes-Farley Verified Community Expert]

That’s good to hear. My goal is to have corals that actually survive.

So low alkalinity isn’t what is causing the corals to leave their skeleton. I’ll leave it alone then, I have enough trouble with the whole thing as it is.

Low alk is a problem. 7 dKH is not low.

 

[thatmanMIKEson]

That’s good to hear. My goal is to have corals that actually survive.

So low alkalinity isn’t what is causing the corals to leave their skeleton. I’ll leave it alone then, I have enough trouble with the whole thing as it is.

Alk is great, i like 7.5-8.5 don't raise it unless you raise you nutrients, your light intensity, and your flow along with it. :)