ALK problems

192clark

Premium Member
175 gal. Sump, external skimmer, sulfur Denitrator, co2 scrubber,

Current stats:
temp -----77.8
PH -------8.2
CA -------540
Alk--------7
SG --------1.024
MG--------1470
No3--------20


My tank has been in sad shape, lack of color, coral frog spawn has decreased from a tank full to very sparce through out. I added the sulfur denitrator to lower No3 that works nicely. Then I added the co2 scrubber to balance Ph. I did all the new equipment after the decline of my tank.

As you can see my alk is low at 7.
Last wk it was 7 and the week before that the same.

The reef chemistry calculator says to add 8 oz Alk. I have done this for 4 wks in a row. Then the next wk it is back to 7.

Ideas please
 
Last edited:

Oldreeferman

New member
Nice size tank there a pic would be cool.

Normal seawater ranges 6-8 dKH so 7 really is not all that bad unless your tank is literally brimming full with fast growing hard corals. I do know most reefers like to keep all params on the high side i do also to a degree.

I have to dose daily to keep a steady dKH of 8.5-9 or else mine would be 7 or even lower so im wondering are you dosing for ALK daily and it simply will not raise?

I use a 2 part but there are several ways in larger DTs that are much cheaper.

All i see is the Mg is high, 1300 is the natural lvl more or less, i try to hover around 1350, mine has been at lvls you now have at one time but it did not cause any ALK issues so doubt that is the issue.
Do you do weekly water changes?
What lighting do you use?
If params are not rock solid a lot of things can all interact mildly at the same time and add up to minor long term issues, i only change 1 thing at a time & wait a month before changing anything else incase i need to pin point an issue such as lighting issues or my dosing params.

That is why im inquiring what salt mix, water change schedule, lighting, how long has DT been setup, and possible dosing amount & schedule you are doing to get a better feel for your situation.

Was the sad shape you speak of due to lack of maintenance?

After you add the ALK dose do you test lateron to see if it worked?

I know if it sours slowly it also takes similar time to get the params back stable again (slowly) and linear again due to coral loss or growth changing intake lvls etc. I removed a large mother colony of Pavona from my sys & it really whacked my params around until i lowered my dosing to match less uptake and the other corals are now large enough to balance that loss finally and im back to my reg dosing schedule again so could be so many things here.
 

192clark

Premium Member
tank set up 15 yrs, 3x 250 Watt DE Metal halide lights. I did make a mistake months back in that I was dosing Kalk instead of ALK which is why CA has gotten so high. I use IO for salt. I use Randy Holmes Farleys two part and never had issues before. Water changes are another area where I got slack. Ive been back on track after this issue started. My tank looks grey/brown very little coraline Algae This issue has been going on for 6 months
 

vosdetailing

New member
I would would buy yourself 3 new test kits cal, mag, alk . With your ph at 8.2 and alk @ 7 something don't seem right. What's your po4 ?
 

vosdetailing

New member
Ok I see you have a c02 scrubber that's why the higher ph, still recalibrate ph probe and test kits and let's see where you @
 

Oldreeferman

New member
Is that IO reef crystals or reg IO sea salt?
I found much better luck with my corals & coralline growth when i switched to the crystals blend and had to dose much less, almost none in a mixed reef.
The wrong dosing may have added to the issue, but long as CAL isnt building up excessively on the pumps or heater its not too high and will lower normally on its own.
On a DT as old as that that has not had reg water changes done always it may have chemicals & minerals accumulating in the water & only frequent water changes can dilute & lower it to a normal acceptable lvl again, (old tank syndrome). A few major water changes back to back might be in order, only way to tell is either just do them say 1/3rd of the water a week 3 times or else have the water tested by a lab to see exactly what is in it before doing anything.
With a tank as old as that id go for a test, its time to see where you stand after 15yrs. since the water was not changed bi weekly by 10% or 20% monthly.
And a good point about using new up to date tests you could have old bad test kits a sure way to go south fast.
 

Sk8r

Staff member
RC Mod
Dose DKH buffer. That should bring it up, given that your magnesium is well over the 1200 'low mg warning' level. Once up, it should not fall. If it does (mg should hold it up) something weird is going on.
 

192clark

Premium Member
I got new test kits for everything, because I thought something was up with others. They were all fine. Po4 is .75 I just added phosban waiting to recheck only on line 2 days. Sunday I added the 8oz of ALK supplement ( reef chemistry calc ). required to raise Alk from 7 -10, today back to 7.
Sk8r I have not used DKH buffer as I am using Randys diy. Is it ok to use the buffer you recommend with Randys

I will do more water changes. Currently 25 gal/wk
Thanks for all of the help Reefers
 

kirblit

New member
I got new test kits for everything, because I thought something was up with others. They were all fine. Po4 is .75 I just added phosban waiting to recheck only on line 2 days. Sunday I added the 8oz of ALK supplement ( reef chemistry calc ). required to raise Alk from 7 -10, today back to 7.

Sk8r I have not used DKH buffer as I am using Randys diy. Is it ok to use the buffer you recommend with Randys



I will do more water changes. Currently 25 gal/wk

Thanks for all of the help Reefers
You don't want to raise your Alk by more than about 1 or 2 DKH per day max and you should do it over a few hours. Raising it that fast is a huge change in water chemistry and would upset many corals. With it dropping out that fast it may just be precipitating back out right after you add it. Try to add enough for 1 DKH and put half in at a time with an hour or 2 between additions and then retest a little later. You should see an increase.

Sent from my SM-G960U using Tapatalk
 

vosdetailing

New member
The p04 many be your whole issue , if you can get that down to at least .10 that would be a good start. 7 - 7.5 alk is not bad so I wouldn't try to hard to reach a #. Focus on your p04 and then everything should start coming together for you. Have you tried nopox? From red-sea
 

outssider

New member
you are very likely having precipitation.....try buffering with sodium bicarbonate (baking soda) instead of the sodium carbonate (soda ash)
 

192clark

Premium Member
Randy's ALK supplement is made with baking soda. The P04 is now at .25. The ALK is now stable. It is still dropping some. I assume it will until my CA lowers more. MG is now 1400
 
Top