Excessive Alk Consumption

[ReefFox93]

Ok so I want to know if anyone has an answer as to why my tank is consuming so much Alk. I have a 2 month old reef (Red Sea Reefer 250) and once it was cycled I got a bit excited and carried away (first reef tank) and added a few LPS corals, couple of morphs and some Zoa frags but nothing huge. Its probably considered too heavily stocked for a young tank but everything is bright and colourful and is growing nicely. The problem is my alk is getting consumed at an alarming rate. In 24 hours its dropping 1.5 -2.0 dKh. If I don't dose for 3 days the consumption rate seems to slow down. I'm testing with both red sea and a Hanna checker. Ive only managed to find one article that makes a little sense where part of the nitrogen cycle which converts nitrite to nitrate consumes Alk and then the Alk gets released back into the tank when the Nitrate is converted into Nitrogen Gas. I was thinking maybe my Sand bed isn't mature enough and isn't converting the nitrate quick enough??

Has anyone had any experience with something like this or can shed some light on what is happening? Only fish in the tank is clowns.

 

[lion king]

What salt are you using and how are you mixing it and at what temp. There is an action we call precip, where calcium and alk react and the levels drop quickly. This can happen with a poorly made salt mix, mixing in too warm water, excessive mixing, and pre mixing too far in advance.

 

[Waters]

Ok so I want to know if anyone has an answer as to why my tank is consuming so much Alk. I have a 2 month old reef (Red Sea Reefer 250) and once it was cycled I got a bit excited and carried away (first reef tank) and added a few LPS corals, couple of morphs and some Zoa frags but nothing huge. Its probably considered too heavily stocked for a young tank but everything is bright and colourful and is growing nicely. The problem is my alk is getting consumed at an alarming rate. In 24 hours its dropping 1.5 -2.0 dKh. If I don't dose for 3 days the consumption rate seems to slow down. I'm testing with both red sea and a Hanna checker. Ive only managed to find one article that makes a little sense where part of the nitrogen cycle which converts nitrite to nitrate consumes Alk and then the Alk gets released back into the tank when the Nitrate is converted into Nitrogen Gas. I was thinking maybe my Sand bed isn't mature enough and isn't converting the nitrate quick enough??

Has anyone had any experience with something like this or can shed some light on what is happening? Only fish in the tank is clowns.

I actually had the exact thing happen to me ( I recently rebooted my mature SPS reef and am using more ALK now, in an empty tank, than I was before with a tank full of growing SPS). I posted in the Chemistry forum and was told that it is pretty common with new sand beds.....sometimes to the point where the sand clumps together and forms "rock". Do you have any clumping that you can see if you stir the sand? If it helps, it has been a few months now and my ALK consumption is gradually reducing.

 

[ReefFox93]

What salt are you using and how are you mixing it and at what temp. There is an action we call precip, where calcium and alk react and the levels drop quickly. This can happen with a poorly made salt mix, mixing in too warm water, excessive mixing, and pre mixing too far in advance.

I'm using Aquarium Systems Instant Ocean (Purple Bucket), I put 25L of RO/DI Water in a Drum with a power head and add salt, This is done at room temp for 10 or so minutes then I check the salinity and add to the tank. I make and store my RO/DI water for a week before my water change day and then add the Salt on water change day.

 

[TripleTruble]

You need to let it mix longer than 10 min. Most salt is recommended at least a couple hours

 

[ReefFox93]

I'll

I actually had the exact thing happen to me ( I recently rebooted my mature SPS reef and am using more ALK now, in an empty tank, than I was before with a tank full of growing SPS). I posted in the Chemistry forum and was told that it is pretty common with new sand beds.....sometimes to the point where the sand clumps together and forms "rock". Do you have any clumping that you can see if you stir the sand? If it helps, it has been a few months now and my ALK consumption is gradually reducing.

I'll have a look to see if i can see any clumping, do I break the clumping up? Will that help. How much has your Alk consumption reduced by and what does it consume on a daily basis now? I want to try and get it under control as I want to add a Yellow Tang soon but not if I'm having swings as I hear Tangs are sensitive

 

[ReefFox93]

You need to let it mix longer than 10 min. Most salt is recommended at least a couple hours

Really, I was told to put a good power head in there until it was crystal clear. I usually let it for 20 minutes but it's usually clear in 10.

 

[ReefFox93]

Just read a link on Precip in another thread, could it be caused by adding to much Alk too quickly therefore raising the Alk Level too quickly?? How would I get back to normal. Just so dosing and let water changes bring up the levels slowly throughout a week or so?

 

[lion king]

Usually the salt is fine to use after it clears, make sure temp is on the cooler side, not more than 78. I would try a different salt, this would indicate to me the salt mix is not stable and you are getting precip. Just to get this right, you test your alk after the water change, and 24hrs later your alk has dropped by that much.

 

[lion king]

Just read a link on Precip in another thread, could it be caused by adding to much Alk too quickly therefore raising the Alk Level too quickly?? How would I get back to normal. Just so dosing and let water changes bring up the levels slowly throughout a week or so?

A good rule of thumb is to not raise your alk by more than 1dkh in a 24hr period. Any changes should be slow as big, fast changes can be dangerous to alot of corals.

What is your target alk?

 

[ReefFox93]

A good rule of thumb is to not raise your alk by more than 1dkh in a 24hr period. Any changes should be slow as big, fast changes can be dangerous to alot of corals.

What is your target alk?

Could that be the cause of precip and explaining my excessive consumption. I was told not to go chasing numbers but from what I've read and watched I was going to aim for 9

 

[Uncle99]

What’s Mg level?
I found when MG is low, it was very hard to keep my alk in line.
When I brought MG to 1360ppm, this problem went away and have no trouble again.

 

[ReefFox93]

Usually the salt is fine to use after it clears, make sure temp is on the cooler side, not more than 78. I would try a different salt, this would indicate to me the salt mix is not stable and you are getting precip. Just to get this right, you test your alk after the water change, and 24hrs later your alk has dropped by that much.

Wasnt straight after a Water change. I got the Alk up to 8.9 with dosing and then tested exactly 24 hours after and it was 6.9. I'm thinking maybe since i raised it to quickly precip may be occurring. I'm going to try not dosing for 5 days and do a Water change to see if I can maybe get the level better by raising slowly

 

[ReefFox93]

What’s Mg level?
I found when MG is low, it was very hard to keep my alk in line.
When I brought MG to 1360ppm, this problem went away and have no trouble again.

Mg is constantly tested at about 1400

 

[Waters]

I'll

I'll have a look to see if i can see any clumping, do I break the clumping up? Will that help. How much has your Alk consumption reduced by and what does it consume on a daily basis now? I want to try and get it under control as I want to add a Yellow Tang soon but not if I'm having swings as I hear Tangs are sensitive

I was told to remove the clumps, but I have just been breaking them up. I only know daily amounts since use a Tident but my SPS tank was using roughly 65 per day. Once I rebooted the system (and removed all coral) I was using over 100 which made no sense. I am back down around 75 now.

 

[ReefFox93]

So just checkes all my parameters and compared them against 48 hours ago

Ammonia 0 - 0
Nitrite 0 - 0
Nitrate 10 - 10
Salinity 35 - 35
Calcium 440 - 440
Alk 9.2 - 6.6
Mag 1480 - 1480

The only thing being used is Alk and it's driving me nuts. I think I'm going to not dose anything and do 10% water changes twice a week to see if I can raise the levels slowly to see if that makes a difference. The only thing I can think of is maybe a raised the level to quickly and its becoming hard in the sand (I have small clumps in the sand, not many but some) and therefore being consumed instead of staying in the water. I'll keep you updated on progress. If anyone has other ideas let me know

 

[lion king]

What I would do, change salts and not dose for at least a week. You could do a few small water changes with the new salt. Be very aware that low alk can be very detrimental to especially lps corals, you don"t see the issue until it is too late.