75 gallon tank alk swing killing corals

darren 9

New member
Recently I felt it necessary to raise my pH and Alkalinity a bit. Unfortunately I believe it did it too quickly and now my corals are dying a slow death - any suggestions - or just let the alk come down slowly and naturally. It has been a week - have not dosed anything - have done a couple small water changes and things are continuing to go down hill.

I believe the parameters are ok now - but I got to them too quickly. Tried to raise over the course of a week.

Original parameters
pH 7.89
dKH 5.5
Ca 480

currently
pH 8.12
dKH 9-10
Ca 380

I have another small tank with parameters similar to original parameters. Is it wise to move some of the corals to it - or will that be as bad as the shock caused by the swing to the higher dKH?

Any suggestions would be appreciated.
 
Just my opinion. I would drip acclimate the coral then transfer to the other tank. ALK swings are deadly for some corals and if you have a stable system that you can transfer the coral into it might be the best thing.

why not try one or two, if there all dieing anyway it might prove the be the solution. see if you get positive results. Best of Luck.
 
What test kit do you use for Alk/dKH? Reason I ask is because I've raised mine by that amount within a couple day time frame multiple times in the past with no issues. I wouldn't think that you'd have that issue by raising it throughout a week. I'm almost wondering if it isn't the swing, but perhaps your current dKH is actually higher than the test kit shows? Just an idea though.

Was anything else changed during that time?
 
What test kit do you use for Alk/dKH? Reason I ask is because I've raised mine by that amount within a couple day time frame multiple times in the past with no issues. I wouldn't think that you'd have that issue by raising it throughout a week. I'm almost wondering if it isn't the swing, but perhaps your current dKH is actually higher than the test kit shows? Just an idea though.

Was anything else changed during that time?

tagging along. I'm wondering the same thing - 4dKH over 7 days doesn't seem outrageous.

couple questions -

- what are you using to dose your tank?
-if it is two part:
------which recipe, what water are you mixing with
------how long do you let it sit?
------do you dose the two parts separately or at the same time
------how much time between?
- when you dose, how much are you dosing at a time?
- when you dose, how much time do you add the dose over (i.e. dump in 50ml, or drip 50 ml)

Hopefully some more seasoned folks will chime in. If it was me I would strive to maintain the current level and make no other changes. measure the tank every morning and evening and dose as needed.

As time goes on you will know how much to dose, in the beginning it takes some effort.

If you are dosing two part make sure to dose equally the KH and Ca. the only time that does not hold true is when you are first establishing good levels.
 
maybe being at 5.5 before was the real problem not the increase to 9.how long do you think it was this low
 
welcome to RC and the URS forum!

welcome to RC and the URS forum!

Original parameters
pH 7.89
dKH 5.5
Ca 480

currently
pH 8.12
dKH 9-10
Ca 380

was there a spike between these two posted values? (ie: did dKH ever get above 10 or pH above 8.12?)

the reason I ask: none of those values should seriously faze most corals. Maybe certain sensitive Acropora would show signs of stress. Most softies and LPS should not be affected much... if at all.
 
Everybody -
Appreciate the responses - and I apologize for the delay in getting back to you all. Let me answer some of the questions posed.

I truthfully had not been dosing anything - and those parameters have been as such for 6-7 months in my 75 gallon and very similar in my 34 gallon which I have grown most of the corals that I am having problems with. I had been doing water changes faithfully every week. My LPS corals such as frogspawn, war coral, several acans were doing very well and growing. And at the time I did not want to mess with it. However - I was having slow growth and color in new chalice corals and two acro's. When I spoke to the LFS and told them my scenario - they thought that the lower alk and pH was likely the problem in addition to not having a good grasp on what the true phosphate levels were. They suggested raising the pH and Alk a bit and skim a bit wetter. Made complete sense to me - and still does in theory.

At that point I added some Kent buffer solution - I did not add the dry powder to the tank - I dissolved the suggest amount in about two gallons of tank water and dripped it in over the period of several hours into the sump.

I am beginning to think that the fatal error was made at that point - the pH and dKH went up and I thought that I needed to continue at that dosing level over the period of a couple days. There were a few days that the dKH was at 11, arguably according to the test kit 12. Calcium over 4 days had gone from 520 down to 440 which made sense to me. All test kits are API.

Took water sample to LFS 7 days later after I noticed things going south - all parameters they said were great - but indicated maybe I did get there too quick. They did not have a phosphate test which I am desperate to find a true reading for.

The corals that are taking the brunt of it are the chalice, frogspawn, favia, and favites, and monitpora. I have an unaffected scroll, bali green slimmer, and the acro are the same as they were. My acans are closed but not really receding. All Zoas and Palythoas are fine. I have a brittle star now that is dropping parts of its limbs and snails are lethargic at best.

I'm thinking at this point I need to stabilize the parameters and keep them there. I have BRS two part sytem now - but need to start it. I am admittedly gunshy. I have ordered the new Hanna Phosphate and Alk electronic analyzers.

I am probably going to have to live with the die off and learn a valuable and costly lesson about the speed at which to change parameters. I think I will stabilize and keep params the same.

The question I have now are there any side issues I should be concerned with after alk nuking my tank - can anyone share some insight about what to look for now. Also any insight about phosphate levels. I am now starting to see some algal growth on the substrate and rock work - fine peach fuzz like stuff.

Again - I appreciate the responses and help - and apologize for the delay in my response.
 
if these are the correct present values

if these are the correct present values

currently
pH 8.12
dKH 9-10
Ca 380

I would topoff for evap with calcium chloride disssolved in RO water until calcium and alkalinity are balanced. Use this online calculator to figure out balanced levels.

Algae growth is normal. Is this a new aquarium? Do you have snails/herbivores?

Do you test for magnesium?
 
Gary
Thanks for the reply. Yes I do test for Mg - has been between 1380 and 1410. Which I believe should be OK. I will follow the info on the link - I hadn't seen that one thanks - I appreciate it. I will advise after a few days. Would you say that the corals that are in demise are likely to die off? I am so disappointed in myself for allowing this to happen. Any comment on the PO4? Should I add a reactor at this point, or straighten this mess out first. I am assuming I should do the later.
 
My bad - to answer one of your questions - tank was started in late June - I had been rock "curing" in another tank for 6 month prior to that. Yes the tank has herbivors in it - Tangs, snails, scarlet hermits....
 
fwiw many chemical methods of reducing PO4 (GFO, Al based adsorbers, LaCl3 etc.) will also reduce alkalinity and I'm not sure that either one is actually a problem in this particular case.

Extremely low PO4 levels coupled with high alkalinity can cause problems with corals. Extreme quick swings in alkalinity can cause problems, too. Seeing how your calcium and Mg levels are good already I would continue to raise calcium (alone) while allowing alkalinity to drift downwards slightly.
 
As far as running GFO to reduce PO4, I would be concerned about adding stress with another rapid change. If you go this route reduce slowly (don't run recommended amount)!
 
As far as running GFO to reduce PO4, I would be concerned about adding stress with another rapid change. If you go this route reduce slowly (don't run recommended amount)!
I agree. Fluctuating alkalinity levels might be the primary cause of all these problems in the first place!
 
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