Think I found the source of my corals on decline! Low alk?

[Flipperfin]

Nearing the half year mark with my 12g nano and everything has been doing great. A week ago however one of my mushrooms started looking very bland and shrivelled up, i thought perhaps it was spawning and moving, but when my tubiopora started looking sad and my GSP also stopped coming out I figured something must be wrong.

I usually do 20% water changes weekly with red sea pro (alk 11.5), and have always had pretty high alk. I only have softies and LPS, and I dont dose.
Today however, I measured alk to be at around 6.4, which seems to me like a big drop? Am i right in assuming this could be the sinner?

I did a tiny waterchange 10% to raise it a little, since im not sure its good to raise it very fast. Im going away for the weekend so I can't stick around and do more small water changes to correct it, but I came up with another idea.

My tap water is of quite nice quality, but has high kh (15.5) (normally use RODI water for top offs), so Im thinking ill use it with my ATO over the weekend (have added aquasafe to remove chlorines etc) to correct the alk slowly - how does that sound for an idea?

 

[ryeguyy84]

sounds like a testing error, have you tried testing newly made saltwater? that's a big drop

 

[EzReefs]

Check your magnesium. If your magnesium is low, you alkalinity will drop. With that being said, I don't think the issue with your mushrooms and gsp is alkalinity. It is likely to be something else.

 

[rtparty]

Unless you KNOW exactly what is in your tap water, you are playing Russian roulette big time. Chlorine/chloramine is just one of a thousand possible issues in your tap water.

Dosing alkalinity is cheap and easy. You can even make home made recipes with baking soda. Do a search on it

 

[Flipperfin]

sounds like a testing error, have you tried testing newly made saltwater? that's a big drop

Yeah I thought so too, but I tested newly made saltwater right after and it showed 11.5 as the label said on the salt :O But it might've happened over a long period as i dont test very often.

Check your magnesium. If your magnesium is low, you alkalinity will drop. With that being said, I don't think the issue with your mushrooms and gsp is alkalinity. It is likely to be something else.

Really? Damn.. I can't really think of what else it could be :/ I dont have a test for magnesium but I guess now could be the time to get one.

Unless you KNOW exactly what is in your tap water, you are playing Russian roulette big time. Chlorine/chloramine is just one of a thousand possible issues in your tap water.

Dosing alkalinity is cheap and easy. You can even make home made recipes with baking soda. Do a search on it

Yeah i intend on start dosing alkalinity, the tap water is just for this weekend while im away . I ran my nano fw aquascape for a year on tapwater without any problems and theres a detailed report from my water provider that doesn't look alarming, so Im hoping it will be fine just for this short period

 

[billdogg]

I'm leaning towards a issue with Mg as well. If it is low, you can dump in Alk supplement until you're blue in the face and it won't budge. Especially in a tank that size, just water changes should be more than enough to keep everything where you need it considering what you have stocked.