Need some insight - Chemistry Guru's

[jimsplace]

I have been having issues with my tank for month's, tried numerous fixes, with no success and finally stumbled on the problem; I have been over dosing my cal and alk by at least 3 times. My dosers are set up on an apex controller dosing once every hour 24/7. My question is; my alk and cal numbers never changed always around 9 and 380, checked with 3 different sources so how come the numbers didn't go thru the roof? I go back through my log and the variations for alk and cal vary very little for months. Were the high levels percipitating out and balancing themselves at the 9/380? I lost most of my sps, but most lps, clam ect were not affected.

[HighlandReefer]

If your alk was actually above 12 dKH, I could see where you could loose a lot of alk and some calcium to precipitation of calcium carbonate. I experienced this when I intentionally raised my alk to about 14-16 dKH. I had to shovel the alk in to maintain this level. When I elevated my alk that high, I experienced a lot of calcium carbonate film developing on my tank glass which was almost impossible to remove. Below 11 dKH I have never experienced that much abiotic precipitation of calcium carbonate. Perhaps check your alk kit to make sure it is reading correctly. Many LFS keep the tops of their kits and such which will reduce the effectiveness of their kits.

If you dosed calcium and alk supplements too close together in your tank at the same time this can result in a lot of calcium carbonate precipitation as well.

There are reports where some hobbyists experience sand hardening in the sand bed perhaps from both abiotic and biotic (bacterial & fungal) precipitation of calcium carbonate which could eat up a lot of alk and some calcium.

Even when I was maintaining an alk level over 14 dKH, I did not experience any problems with my coral. Research backs this. You will experience an increase in growth of sps coral while maintaining an alk level above say 12 dKH & up. ;)

[chuckreef]

Why do you think you were overdosing?

[jimsplace]

If your alk was actually above 12 dKH, I could see where you could loose a lot of alk and some calcium to precipitation of calcium carbonate. I experienced this when I intentionally raised my alk to about 14-16 dKH. I had to shovel the alk in to maintain this level. When I elevated my alk that high, I experienced a lot of calcium carbonate film developing on my tank glass which was almost impossible to remove. Below 11 dKH I have never experienced that much abiotic precipitation of calcium carbonate. Perhaps check your alk kit to make sure it is reading correctly. Many LFS keep the tops of their kits and such which will reduce the effectiveness of their kits.

If you dosed calcium and alk supplements too close together in your tank at the same time this can result in a lot of calcium carbonate precipitation as well.

There are reports where some hobbyists experience sand hardening in the sand bed perhaps from both abiotic and biotic (bacterial & fungal) precipitation of calcium carbonate which could eat up a lot of alk and some calcium.


Even when I was maintaining an alk level over 14 dKH, I did not experience any problems with my coral. Research backs this. You will experience an increase in growth of sps coral while maintaining an alk level above say 12 dKH & up. ;)

Cliff,
During my trouble shooting efforts, I tested the water numerous times with 2 different kits, and by the lfs always tested at 9+\- and 370-400. I had started getting a lot of precipitation on my pumps and quit dosing kalk which helped. I was dosing as much as 170-180 ml per day. It puzzles me how I could not be getting high alk readings. All my other prams seemed to be in line as well. Some alage (nothing serious) issues and started BRS biopellets about a month ago. N & P are below the lowest reading on my salifert kits. Just really strange.

[funkejj]

What is your Mag? If Alk and Calcium are not moving it might be low mag.

[Habib]

quit dosing kalk which helped

High pH by dosing kalkwasser (calcium hydroxide) will cause precipitation at lower alk and calcium values. Because a high pH transforms bicarbonate to carbonate.

[bertoni]

Yes, and the same problem can occur with the high-pH two-parts. For some tanks and dosing situations, the low-pH version is better, but you might need to dose into a different part of the tank or add more circulation. Buildup on pumps and heaters is a primary sign that the supplements are precipitating on their own.

[jimsplace]

Guys,
I cut my dosing in half last week (to about 80-90ml), tested and the alk was still at 9, cal dropped a little to about 350 (probably noise). Have since dialed back the dose to about 60ml. I will continue to dial back the dosers to see at what point my alk starts to drop and hold at that level. I still haven't heard anyone comment on why the alk/cal numbers wouldn't be extremely high with the amount being (over)dosed. Mag runs 1350+/-. Stopped kalk dosing several months back. Am dosing BRS soda ash and cal, ph runs 8.0x-8.2 and added a BRS bio pellet rx about month and half ago. Some of the corals (whats left) have started to show some color so I'm pretty sure they were reacting to the overdosing.

[bertoni]

Okay, well, I'm glad to hear the corals are looking better.

[reefology]

I still haven't heard anyone comment on why the alk/cal numbers wouldn't be extremely high with the amount being (over)dosed.

i believe habib did, followed by bertoni. likely dosing soda ash and/or kalk at night during ph depression (commonly and logically recommended), so guessing you're not around to notice the ph spike. if that isn't it and your mag #'s are correct, then I'm stumped and would love to hear someone else chime in.

cheers

[jimsplace]

i believe habib did, followed by bertoni. likely dosing soda ash and/or kalk at night during ph depression (commonly and logically recommended), so guessing you're not around to notice the ph spike. if that isn't it and your mag #'s are correct, then I'm stumped and would love to hear someone else chime in.

cheers

I dose 24/7 using my apex and looking at the graphs, ph never spikes, normally I see a range from 8.0x to 8.1x and occasionaly a little over 8.2. The kalk questions are n/a because dosing stopped 2-3 months ago. My mag levels are usually at the 1300-1350 range which is normal I think. So, yea I been stumped too and have spent 100's of dollars on various fixes none of which helped. Only discovered the possibility of overdosing by talking we a fellow reefer who has much more sps and only doses half of what I was. It is my belief that somehow the alk and cal were precipitating out and and somehow reaching an equilibrium as I noted my logs never showed much variation. But there must have been a byproduct of this producing something harmful to my corals????????

[bertoni]

There should be some calcium carbonate buildup somewhere. The issue might not be a pH spike throughout the tank: locally high pH can be a problem, too. That typically occurs when dosing into a small sump or perhaps the return chamber. The supplement went somewhere. There could be a lot of buildup in places that aren't easily visible.

[jimsplace]

There should be some calcium carbonate buildup somewhere. The issue might not be a pH spike throughout the tank: locally high pH can be a problem, too. That typically occurs when dosing into a small sump or perhaps the return chamber. The supplement went somewhere. There could be a lot of buildup in places that aren't easily visible.

Yes I have had calcium build up on numerous things; pumps, skimmer, reactors .... I have moved my ald dosing to the DT high flow area, still dosing cal in my sump. I can understand the precipitation, but how does that relate to my corals dieing?

[HighlandReefer]

The negative effects from overdosing soda ash can be increased pH if too much is added at one time. A pH over 8.5 will cause problems for coral.

The other possible negative effect would be from the contaminates in the soda ash. The heavy metal contaminates can be in the toxic ionic forms which if too much is added can have negative effects on your coral, particularly copper. This would be my biggest suspect for you coral problems.

[reefology]

I have to say, there is so much to be learned in this forum...Great job guys!

I have a couple questions in regards to responses from Jon and Cliff.

1. even if there is local precipitation, shouldn't we still see a ph spike somewhere? note the threadstarter has a controller monitoring 24/7. Guess he could be dosing in a very low flow area but i doubt it???

2. contaminates in the supplements are definitely a concern when over dosing that suddenly as apposed to accumulation over time. What supplements are you using?

cheers

[jimsplace]

I have been dosing in my sump, plenty of flow there.
I dose BRS soda ash and calcium and add their mag when needed rarely.

Cliffs comments about heavy metals is scary, never heard that before. Maybe when I run out of soda ash I will try some good old A&H BS for my alk supplement. This has been the strangest trip trying to figure out what went wrong with my tank. I have lost most of my corals ($1000+) and have spent untold more on various fixes. I have tried everything so at least now I think I am on the right track. I was seeing a lot of calcification in my sump equipment, GFO reactor, powerheads etc... nothing really in my tank other than the LR looks like its been dusted. Thanks for everyones thoughts and input, keep them coming if you can think of anything more.

[reefology]

Jim, I'd like to point out that the BRS soda ash is apparently pharmaceutical grade and Arm and hammer is food grade so i'd stick with the BRS product for now...even though they haven't released a list of impurities (at least not to my knowledge).

I too think you're on the right track with the help of these guys, they really know their stuff :)

cheers

edit: btw i still don't get how you didn't get a ph spike even though you noticed precipitation on all equipment and rock??? As far as I know, it's the increase in ph that triggers the event? perhaps someone can clarify.

[HighlandReefer]

Jim,

Sorry to hear about your loss of your coral. That is a lot of money too. Needless to say this is very frustrating. :(

I think the important thing is that you seem to have figured out that you were overdosing the alk supplements. If you were indeed overdosing your alk, calcium carbonate had to precipitate out very quickly to not see an increase in your tank alk level. You did see a lot of precipitation on your equipment....etc.

Switching to baking soda since it does not effect pH much, will certainly reduce the likelihood of calcium carbonate precipitation & any negative effect from too high a pH from using sodium carbonate. So it should reduce the likely hood of overdosing due to high amounts of precipitation.

As far as the heavy metals, Randy provides much more details regarding this in this article noted below. If you were adding three times the amount of sodium carbonate, this could have pushed your heavy metals too high.

Reef Aquaria with Low Soluble Metals
http://reefkeeping.com/issues/2003-0...ture/index.htm

[HighlandReefer]

One thing about the different food grade and even pharmaceutical grade chemicals is that the tolerance level of copper, for example is higher than we like for a reef aquarium. This does not mean that the chemical has those high max. levels, in many cases the copper can be much lower than the max. tolerance level.

The main reason why dosing supplements has maximum recommend levels to add in a given period of time is due to the heavy metal levels even in the higher grade chemicals. This gives the heavy metals like copper time to attach with organic dissolved chemicals in the tank water where the toxicity is greatly increased. Too much at one time can drive the heavy metals up for periods of time that are extremely toxic to coral. It does not take very long for coral to react negatively when the level is increased high enough, perhaps even as low as 20-30 ppb copper for many coral and for some other perhaps less.

FWIW, using lime water is most likely the best to use for dosing since it is self purifying regarding copper & some other heavy metals, although increased precipitation due its high pH like sodium carbonate may result in overdosing.

[tmz]

I think it was precipitating which causes bounces in the alkalinity which are harmful to sps,ime.

[reefology]

bounces in alkalinity...harmful??? please explain.

[jimsplace]

Cliff, your link didn't work for me. Will the metals you described be a long term issue? If copper was the culprit, I think would see fewer cucs.

tmz, I can go back through my logs for a year and no real spikes in alk, occasional variations (8.5-10 probably noise) but week after week it ran 9+/-. My calc varied more and continue to manual dose to keep the levels up. I had/have a hard time keeping calc at or above 380.

Based on our discussions, I think maybe the precipitation was more localized in the sump area, because I never saw anything in the DT. The corals would mostly brown out and die. The montis seemed esp hard hit as were numerous other sps. Didgis and a slimer seemed to survive. lps did't seem bothered much and my clam continues to grow.

This is a great forum, appreciate all the input you guys are giving. I guess as the old saying goes, "time heals everything". I am determined to solve this mystery.

[HighlandReefer]

Sorry the other link did not work. ;)

Reef Aquaria with Low Soluble Metals
http://reefkeeping.com/translations/finnish/2003-04/artikkeli.php

[jimsplace]

Cliff,
This one works but in another language, with no english translation available.

Thanks, Jim

[HighlandReefer]

That's great. I need another cup of coffee. :lol:

Try this one:

http://www.reefkeeping.com/issues/2003-04/rhf/feature/index.php

[GlenG]

IME if I ever had rtn/stn on sps it always happened after a sudden drop in alk.

[bertoni]

The precipitation might have caused some bouncing in the alkalinity levels, which I agree seems to cause problems. The problem might lie elsewhere, though. The precipitation might have been quite gradual, for example. It's hard to be sure.