trying to understand Alk and Calcium 'balance'

[fishman]

Steve
I dont expect you to remember this but I lost my 125 to a leak and had to transfer all my stock over to the 100...I swapped from CC to sand...I have about 2-3 inches sand now. I also lost a lot of my old water from the 125 as well.. I used about 85 gallons from the 125 and mixed up another 55 gallons of new water to go into the 100 gallon (as it has a 40 gallon sump/fuge). This was 1.5 months ago so I have not done a water change as i wanted everything to stabalize. Otherwise I was doing 2 water changes a month....of about 20 gallons per change in the 125.
Also I have been using instant ocean for 2 years...

 

[steve-s]

Twice monthly water changes would normally be acceptable for an FO system in regards to the chemistry. It really depends on the waste created and typical nitrate levels as well but for the most part it's just fine.

The only issue I have with IO is the imbalanced chemistry. As I said for the most part an FO system is not that much a concern but the typical backwards chem (high alk, low Ca) can leave a large margin for things to go awry.

Also FWIW, the buffering capacity of a CaCO3 based substrates while always a plus will only marginally maintain alkalinity and should not be relied upon.

Cheers
Steve

 

[malkore]

Yeah, i'm using IO salt, but switching to Oceanic as soon as these last few cups are used up. In fact I'm mixing IO and Oceanic 50/50 right now for water changes, so it's more gradual.

 

[steve-s]

I wouldn't suggest mixing the salts. You'll end up with more problems than you'd solve. Best suggestion is to do your water changes as normal but only change ½ the amount you normally would, ie.. 5-10% instead of 20%. If a reef system, do this over a period of 6-8 weeks and then gradually increase the amount changes as the weeks go by until your back to normal.

For an FO or FOWLR this is not as important but with corals and sensitive inverts, switching saltmixes can have serious reprocussions. It's not just the alk/Ca but also the rest of the major/minor trace element changes and "tweeks" in pH.

Be wary...... 8O

Cheers
Steve

 

[MarineFlake]

Check your mg, should be around 1350ppm. If it gets low, you can have severe flux in ca/alk. (Typical symptom: "I've dosed ca now for 2 weeks (etc) and I can't get my ca over xxx) mg is sort of a buffer if you will, for the the ca. Get a good (salifert) mg test, and post the results. That will help determine if you are just spinning your wheels. Also, not sure who posted it, but I have never heard of killing an invert due to a rise in ca. A few pumps maybe, but never an invert or other animal for that matter. Sharp rises in certain trace elements can and will cause molts (Both inverts and coral). Just because I haven't heard of it doesn't mean it can't happen, but if there is any reading on that, someone post.

 

[steve-s]

Also, not sure who posted it, but I have never heard of killing an invert due to a rise in ca..

Where is this thread did you read that

Cheers
Steve

 

[fishman]

I think he is referrring to me saying that I think I killed a cleaner shrimp due to adding to much buffer to fast. I didnt pour it in like I have done in the past....I mixed the buffer with tank water and was in a hurry and all but dumped the water and buffer into the sump....Just my thought at least as the cleaner seemed very dazed and wouldnt move around much...he was gone the next morning so I assume he died and the clean up crew ate him...

 

[malkore]

Well today:
Alk: 2.5meq/l
Ca: 325ppm
pH: 8.0 (tested right after lights on)

I'll get that magnesium kit too, it's the only one (besides iodine and strontium) that I don't have, and since I only have 2x96 PC over a 40gallon, I'm guessing I'll never be able to keep corals that would require Iodine and strontium testing.

 

[steve-s]

I think he is referrring to me saying that I think I killed a cleaner shrimp due to adding to much buffer to fast. I didnt pour it in like I have done in the past....I mixed the buffer with tank water and was in a hurry and all but dumped the water and buffer into the sump....Just my thought at least as the cleaner seemed very dazed and wouldnt move around much...he was gone the next morning so I assume he died and the clean up crew ate him...

Adding to much buffer or increasing alkalinity too quickly can indeed affect invertebrate health. Alternately large additions of Ca will not harm inverts as long as it's stays relative to NSW. Only when Ca is too low or raised too high outside NSW can it become damaging.

Cheers
Steve

 

[steve-s]

Well today:
Alk: 2.5meq/l
Ca: 325ppm
pH: 8.0 (tested right after lights on)

Looking better from 270 ppm a few days ago. As long as the alk stays steady you should have no problems.

ince I only have 2x96 PC over a 40gallon, I'm guessing I'll never be able to keep corals that would require Iodine and strontium testing.

There's no reason why you could not have a diverse group of corals with that light. The only thing you should stear clear of would be SPS's, clams and certain anemones. As far as iodine and strontium, they don't truely need dosing so there not much reason to test for them.

Cheers
Steve

 

[MarineFlake]

This was the post in this thread I was referring to. He mentions specifically adding ca in conjunction with the death of an invert. "...and accidently added the CA to fast the other day and did in one of my cleaner shrimp..."

Not to hijack this thread, but rather right along the same line...My CA has been 280-300 now for 2-3 weeks...Salinity is 1.025, temp 80-82, PH 7.9 up to 8.4, Akalinity 2-2.5.. I cant seem to get my CA and alkalinity up for anything. Plus my rock has lost its color and prior to me switching all of the inhabitants and such from a 125 to a 100, I had coraline growth that was awesome...now its all fading and nothing is growing.. I have never had to add buffer as i had CC in the previous tank. Now I add Seachem CA, kent Super Buffer, and accidently added the CA to fast the other day and did in one of my cleaner shrimp...I have hit a wall for sure...I have 4 small fish (perc size) and 1 anenome, 3 shrimp and 150 lbs of LR.

 

[steve-s]

"...and accidently added the CA to fast the other day and did in one of my cleaner shrimp..."

Sorry PC, I honestly missed that part.

Cheers
Steve

 

[blorkiemom]

Theatrus and steve-s--going back a couple of pages--thanks for the links!

 

[fishman]

Sorry guys my bad...I meant that I added CA and then a few hours later I added buffer and I think THIS is what killed the invert....I added the buffer to fast...I know the CA didnt do it...I think my fingers were typing to fast.. Its the buffer that did him in.