SPS dying


New member
I need help. My SPS's are looking terrible. My milliss tip appear to be receeding downward. My green and purple caps have a brownish tint to them. My green especially appears to be loosing color. I can not figure it out. I see no bugs on them at all.
Everything else is doing fine.

Calc 400-410
Mag 1280
Alk somewhere in the range of 1.7- 2.0, I think. It is a color chart test kit.
Ph 8.2
Salt 1.025





New member
I know my alk is low but I can't seem to raise it. I have been trying baking soda. Also my calc has not dropped in weeks.

Alaskan Reefer

New member
It sounds like your Alk is being burned through as fast as you add it -- to the point where it's low enough to hinder calcification / overall health. What is your supplementation regimen for Ca and Alk?


New member
With a 90gallon system volume it takes 12tsp of sodium bicarbonate to raise the Alk from 2meq/L to 4meq/L. Have you added this much?


New member
Alaskan Reefer I was dosing Tropic Marin Bio Calcium but stopped because my cal was never dropping.

Marsfrogie I have not added that much. Does it matter if I add it all at once?

What could be causing my Alk to be used up so quickly??


New member
Sodium Bicarbonate has a slight lowering effect on pH. Just monitor your pH. I have added that much before on a smaller system with no ill effects but I don't feel comfortable telling you to do the same.


New member
If I don't supplement with anything my alk drops 50% in one week due to demand. It is not uncommon. You will have to dose Ca and Alk regularly to keep stony corals.

I am not sure exactly what is in Tropic Marine Bio calcium. From the product description, it says it will add all the "calcium carbonate" your corals will need. I don't know how to take what they are stating. If their mix contains only calcium carbonate, this will not supply any usable calcium for your corals. If they are implying the coral production of calcium carbonate, then that might be a different story. The manufacturer also states it will add other micro-nutrients which IMHO are normally not necessary. Salt mixes are already high in the micro-nutrients. There is nothing on the label that makes me believe that this product will increase your alk.

I would use the Reef Chemistry Calculator to determine how much baking soda you need to add to elevate your alk. to your desired level. You should not raise your alk. by more than 2 dKH. This may take several days. Once your alk. level is where you want it, it will be trial and error to figure out how much you will need to add daily. If your alk. drops too low, then use the calculator to determine how much to add to bring it back up. If it gets to high, then stop dosing until it drops where you want it.

Reef chemicals calculator


Premium Member
I had a similar problem a few yrs ago. I had to add a hole quart of B-ionic Alk (over a few weeks) to make up the difference. But my level wasn't that low, it was slightly low and my Ca was high. So it took a few weeks to even out.

I have never used baking soda, so I can't say how long I think it will take. But for future dosing you will either want a DIY 2 part, or a commercially available 1. You might also want to check your Mag level while your straightening everything out.


ReefKeeping Mag staff
Premium Member
Baking soda works great and works quickly. If you bake it first and blow of the CO2 it will have a slight ph raising effect. Unbaked it has a slight ph powering efffect due to the CO2 it has absorbed from the air.

Have you checked your nitrate and phosphate?. High levels of either could account for the sps dying.


New member
My phosphate is 0. I have not checked my nitrates.

HighlandReefer--- I was under the impression that the Tropic Marin product did the same as a two part mix. I was misinformed. I will take the blame because I did not read the package. I used to use the B-ionic two part and never had an issue. I feel like an idiot!!! Do you think rasing the levels back up will save my corals? That pink mili is about 10" and the green cap is about 12".


New member
I have had a chalice that looked similar to yours due to an alk issue and it recovered fine. Trick is get the alk up to where it needs to be now...

rick s

Premium Member
Just to add to what's been said: How are you measuring pH? With a meter? Have you calibrated it lately? I had similar issues when my pH got too low.


New member
<a href=showthread.php?s=&postid=14829894#post14829894 target=_blank>Originally posted</a> by bill37
My phosphate is 0. I have not checked my nitrates.

FWIW, I've seen nitrates over 5ppm do just what you are describing: pitiful growth and browning out.

If your phosphates are truly 0, then most likely your nitrates aren't all that high either, but you still want to test it and be sure.

IMO nitrate almost tops the list of most important things to check.


New member
rick s I use a meter. I just calibrated it last week.

redfishsc I haven't checked my nitrates in months. Yikes. I will check tonight.

Thanks everyone.

The baking soda has gotten my alk up to par I think. The test kit I am using is Red Sea. It has a color chart to compare. There are three sections
Low----- 0 - 1.6
Normal----- 1.7 - 2.8
High------ 2.9 - 3.6

Mine appears to be in the higher part of normal. measured in meq/lt.
I hear conflicting thoughts of what is a good level. Any suggestions?