At my wits end

[NaturalViolence]

Double post time.

 

 

If precipitation and accretion are rapid enough, it will never have the opportunity to form. Older sand that is already an actively growing crystal will cause this.

 

Can you prove this though? This does not make sense. There is no way that precipitation can outpace bacteria under these conditions nor can it stop bacterial growth completely.

 

Under favorable conditions they do. Seawater is supersaturated with respect to CaCO3 to begin with.

 

But it's not anywhere near that rapid. My rate of depletion was at least 50 times what it should be. Even with completely dry/dead sand/rock precipitation still occurs very slowly during the first week. This points to it being the "conditions" as you put it instead of the sand that are the cuprit.

 

See the above. Live sand can help by reducing the surface immediately available.

 

Immediatly? Maybe. Long term? I doubt it. Any dry sand should eventually develop the same biofilm as live sand under the same conditions.

 

Common with limewater if pH isn't monitored carefully. Localized pH on some surfaces can be even higher due to photosynthesis and CO2 depletion.

 

The weird thing is I was monitoring PH and saw no change. Which seemed to imply that I was dripping it slow enough. And precipitation from high PH shouldn't become a big issue until you hit 8.5+, which I definitely wasn't.

 

Can be caused by overdosing just about any supplement, but relatively common yes.

 

Only high PH additives.

 

Sounds like you've answered your own question here. In your case, it sounds more like a pH issue possibly coupled with overdosing and a nice area for crystal formation.

 

I'm still not sure. PH seems to be the dominant culprite because slow dripping did not help. However if that's the case why wasn't it detectable?

 

GFO is fairly basic, so unusual that it would dissolve. It should barely move in the reactor. Just enough to keep it from clumping. Sounds like it pulverized and the localized high pH of the particles caused issues.

 

Indeed. However I tried to mimick the flow I was seeing in other reef tanks. If anything it was lower than what I was seeing from other tanks. The tricky thing is the GFO near the top of the reactor moves much more than the GFO near the bottom. To the point where the top portion was being pulverized while the bottom portion was clumping. I'm not sure if I'll give it another shot. I didn't really see any reduction in algae growth while I was using it. Right now I've converted it into a carbon reactor.

 

This is actually a balanced additive. You shouldn't be adding an alkalinity additive with calcium gluconate.

 

That's not what it says on the bottle or the website. How could polygluconate raise alk?

 

Do the flakes redissolve? Solid, larger flake formation isn't really that normal, IME. There should be some very momentary precip in the area of the addition, but this just looks cloudy with minimal crystal formation.

 

Impossible to say. I would have to show you. They weren't very large or very solid. They seemed to redissolve but since the pumps quickly blow them out of way it's hard to tell. It seemed to be the same as what everyone else experiences.

 

Fairly normal, as they are antagonistic with respect to concentration beyond a certain point. An alkalinity of 7.5 and calcium concentration of 420 is perfectly acceptable, btw. Very close to NSW values, actually.

 

I know. However that's not as high as I wanted and just to maintain those levels I was using a lot more supplements than I should have to.

 

This is what I dose now, not only due to its comparatively dilute nature, but I have a lot of light and photosynthesis which drives pH fairly high otherwise. I have a fair amount of plant growth, as well.

 

It's almost as if there is no CO2 in the system in my case. It would explain why any carbonate or hydroxide additives just drove precipitation since there was no CO2 around to convert it into HCO3 and CO3. It would explain everything. But if that were the case I would expect to detect a high PH. And I have plenty of surface agitation and aeration in my system (including a protein skimmer) so even with lots of macros consuming CO2 you would the atmospheric dissolution to replenish it fast enough.

 

That is a possibility. Increase aeration will also introduce CO2, however.

 

Yes but it should not increase it beyond the saturation point with earths atmosphere (which if I recall is around 1/10th of atmospheric concentration?). Thus the PH/alk should not drop unless the air being pumped in is too high in CO2. And this is outdoor air so that should not be possible.

 

 

I'm glad that I fixed it but the solution still doesn't really make sense based on my observations.

[Lynaea]

I'm wondering about the temperature variations from the tank being outside.

 

The tank you're having issues with has a sump and therefore external pipes or tubing. Seems like all that surface area would lead to greater temperature swings than in the self contained unit. It also sounds like the Alk is self correcting back to a certain level.

 

Obviously salt makers assume most tanks will be kept at a stable temp of around 80 degrees and of course try to mimic ocean conditions at this temperature. Lots of other things are temperature dependent; oxygen carrying capacity, salinity, pH (?).

 

Could it be possible that the temperature swings are affecting the Alk / calcium levels without actually removing them, maybe just changing them to a form that is unavailable and undetectable by your test kits but still in solution?

 

Or is it possible that the unstable conditions as a whole are the cause of the slow LPS growth and the weird Alk deficiency is just part of the equation?

 

I also keep wondering about the DSB, is it possible that at certain temperatures the minerals that support Alk are absorbed or adsorbed by individual aragonite grains? Not to the point of forming accretions but just a little bit over many thousands of grains........

 

I am definitely speculating based on water chemistry as I understand it so I could be way off base but the calcium, etc can't just be crawling out of the tank

[Lynaea]

Okay, I'm back with research. From Wikipedia so.....

http://en.m.wikipedia.org/wiki/Alkalinity

 

First, anaerobic processes increase alkalinity but aerobic processes decrease it (because they form acids and the Alk is used up buffering the pH). If the DSB in your tank is not deep enough, or fine enough or whatever to form an anaerobic zone its possible it is singlehandedly lowering the pH enough to drive down the Alk, or maybe this process is temperature dependant too (most likely) and it's just too hot or???? This would actually explain your apparently stable pH.

 

Also: "Oceanic alkalinity also follows general trends based on latitude and depth. It has been shown that (Alk) is often inversely proportional to sea surface temperature (SST). Therefore, it generally increases with high latitudes and depths. As a result, upwelling areas (where water from the deep ocean is pushed to the surface) also have higher alkalinity values.[15]"

I'm not 100% sure how this pertains.

 

My guess would be some process is pulling down your pH which is being buffered by the available Alk, you then have to dose a lot to overcome this Alk sink. Do you have a lot of detritus, algae, .....?

[Amphiprion1]

Double post time.

 

 

 

 

Can you prove this though? This does not make sense. There is no way that precipitation can outpace bacteria under these conditions nor can it stop bacterial growth completely.

 

On the contrary, how can an instantaneous, persistent abiotic reaction not potentially outpace bacterial activity, especially under favorable circumstances? Biofilms can take a longer to form than you might think, unless there is something present to cause a dramatic increase in growth. I do not understand your reasoning as to why this does not or cannot occur in instances like your tank's situation. FWIW, nowhere did I say nor imply that it could stop or even slow bacterial growth.

 

 

But it's not anywhere near that rapid. My rate of depletion was at least 50 times what it should be. Even with completely dry/dead sand/rock precipitation still occurs very slowly during the first week. This points to it being the "conditions" as you put it instead of the sand that are the cuprit.

 

How is it not that rapid with consistent scaling, sand clumping, etc.? It's still sounds like both, with the pH and/or overdosing being the main cause. A crystal that doesn't have a biofilm will encourage rapid precipitation in an already supersaturated solution. The conditions in your case only accelerate what is already occurring and what would normally decline and stop over time--and it is providing a large surface area on which to do it. It's acting like a negative feedback system with the general conditions and constant, heavy supplement addition.

 

Prior to the further information you provided, I wasn't aware of the other issues, which is why I originally suspected that the sand might be a problem.

 

 

Immediatly? Maybe. Long term? I doubt it. Any dry sand should eventually develop the same biofilm as live sand under the same conditions.

 

See the above. With the both the speed of abiotic precipitation and persistence of CaCO₃ additions, you could just about perpetuate it.

 

 

The weird thing is I was monitoring PH and saw no change. Which seemed to imply that I was dripping it slow enough. And precipitation from high PH shouldn't become a big issue until you hit 8.5+, which I definitely wasn't.

 

Not necessarily always true. There is a lot that determines solubility and you may still be overdosing with respect to CaCO₃.

 

 

Only high PH additives.

 

No. Overdosing just about any additive, especially balanced ones, can result in precipitation. More common with those that have higher pH. The equilibrium can be shifted by manipulating [Ca++], [CO₃, or pH, leaving plenty of room for error.

 

I'm still not sure. PH seems to be the dominant culprite because slow dripping did not help. However if that's the case why wasn't it detectable?

 

If it is high enough and you continually add hydroxide, the precipitation will consequently lower both pH and CaCO₃, likely masking the effect. FWIW, GFO has this effect as well, especially when enough is added. GFO itself has a high local pH and it causes a subsequent drop in pH in the system due to initial amounts of localized precip.

 

 

Indeed. However I tried to mimick the flow I was seeing in other reef tanks. If anything it was lower than what I was seeing from other tanks. The tricky thing is the GFO near the top of the reactor moves much more than the GFO near the bottom. To the point where the top portion was being pulverized while the bottom portion was clumping. I'm not sure if I'll give it another shot. I didn't really see any reduction in algae growth while I was using it. Right now I've converted it into a carbon reactor.

 

Good call, given the situation. A system already experiencing precip, etc. should do without GFO, as it may cause it to bind/clump. It will also encourage more precip initially. Do without for a while until everything is more under control.

 

 

That's not what it says on the bottle or the website. How could polygluconate raise alk?

 

My fault here, as I misread. Polygluconate won't, but calcium gluconate will when it is degraded via bacterial action. A residual hydroxide ion is one of the final products, much like calcium acetate, which is also a balanced additive.

 

 

Impossible to say. I would have to show you. They weren't very large or very solid. They seemed to redissolve but since the pumps quickly blow them out of way it's hard to tell. It seemed to be the same as what everyone else experiences.

 

Okay.

 

 

I know. However that's not as high as I wanted and just to maintain those levels I was using a lot more supplements than I should have to.

 

Unfortunately, parameters are not always going to be cooperative. I would suggest aiming for anywhere within the appropriate ranges for both and not try to shoot for anything specific within those ranges.

 

 

It's almost as if there is no CO2 in the system in my case. It would explain why any carbonate or hydroxide additives just drove precipitation since there was no CO2 around to convert it into HCO3 and CO3. It would explain everything. But if that were the case I would expect to detect a high PH. And I have plenty of surface agitation and aeration in my system (including a protein skimmer) so even with lots of macros consuming CO2 you would the atmospheric dissolution to replenish it fast enough.

 

Yes, without CO₂, pH would be fairly high.

 

 

Yes but it should not increase it beyond the saturation point with earths atmosphere (which if I recall is around 1/10th of atmospheric concentration?). Thus the PH/alk should not drop unless the air being pumped in is too high in CO2. And this is outdoor air so that should not be possible.

 

Yes, you cannot increase beyond what is feasible based on pCO₂ in the atmosphere, being outdoors. The alkalinity won't be affected based on dissolved CO₂ (solubility will), just pH and only in a system that is not equilibrated or is limited with respect to CO₂.

 

I'm glad that I fixed it but the solution still doesn't really make sense based on my observations.

 

It makes sense to me based upon what you are describing, but it's always possible I'm over-complicating things.

 

See reply in red.

[NaturalViolence]

It's doing it again. I have a new theory now.

 

My protein skimmer pump impeller broke a couple days before I made the switch to bicarbonate. As a result I went a week without a skimmer while the new impeller was shipping. I also didn't feed anything during this week for fear that the water would foul too quickly without a skimmer. Recently the alk has once again suddenly started dropping back down to 7.5 regardless of dosing. I believe the timing of this coincides with me fixing the skimmer. So I believe the skimmer is somehow to blame for the low alk. Maybe there is something in the air? This makes even less sense than before. Dear god this tank is cursed.

[Amphiprion1]

Yeah, it's beginning to make little sense. So it coincided with fixing the skimmer and not going without? Possible that going without skimmer allowed CO₂ to rise...?

 

I think at this point it may be wise to stop adding anything and stop waterchanges. Your corals should be fine for a while, even if the levels slip below normal a bit. I would let them fall naturally and carefully supplement after the fact and see what happens.

[NaturalViolence]

I just remembered something. Back when I had to mix up my own alk mix and dose crazy amounts in the sump everyday the skimmer would go nuts for awhile afterwards. I wonder if somehow the skimmer is removing some of it. It doesn't make sense chemically though.

 

Well at least I finally got a dosing pump. I'll hook it up tomorrow and start dosing in the main tank instead of the sump. If that doesn't work I'll have to try removing the skimmer again and see if I can repeat the results. It would be a real shame though as this is the cleanest that my tank has ever been. The SPS corals seem to have stopped growing the last few days, coinciding with the low alk. They grow 0.5mm a day (1mm in the case of my monti, yes my measurements are that precise) if I can just keep the damn levels up. I would track the other tank more closely now to verify that it's only happening to the reef tank. If it's happening to both tanks then it might be something in the air. In which case I guess I could try running the skimmer air intake through an activated carbon air filter.

[Tamberav]

In regards to GFO. In my reactor I mix GFO with carbon, at least 50% of it must be carbon though. The more carbon the less chance of clumping. This works great and no need to tumble it, run it like you would carbon.

[NaturalViolence]

Another quick update (I will eventually get around to responding to the above posts, I promise). Dosing in the main tank has appeared to have slowed it down though not eliminated it. And I've noticed quite a bit of precipitation coming back in the return section of the sump which is right next to the skimmer outlet.

[NaturalViolence]

Sorry for the double post.

 

I've done some more testing. It is now happening in both tanks. This is particularly strange since the other tank doesn't have a skimmer right now (I unhooked it a week ago). Maybe it does have something to do with the temperature? We're right in the middle of summer right now so tank 1 peaks at around 89 F at midday and tank 2 (reef tank) at around 86 F. None of my organisms have shown any signs of stress as a result. I do know that increasing temperature reduces solubility of calcium carbonate and therefore promotes precipitation. But I wouldn't think a few degrees would make such a big difference. Without a couple hundred bucks for a chiller I have no way to test this either.

[Tamberav]

Sorry for the double post.

 

I've done some more testing. It is now happening in both tanks. This is particularly strange since the other tank doesn't have a skimmer right now (I unhooked it a week ago). Maybe it does have something to do with the temperature? We're right in the middle of summer right now so tank 1 peaks at around 89 F at midday and tank 2 (reef tank) at around 86 F. None of my organisms have shown any signs of stress as a result. I do know that increasing temperature reduces solubility of calcium carbonate and therefore promotes precipitation. But I wouldn't think a few degrees would make such a big difference. Without a couple hundred bucks for a chiller I have no way to test this either.

 

Use a fan.

[NaturalViolence]

I already do:

 

Equipment:

6" fan over refugium for evaporative cooling. 300w heater. Skimmer is an SCA-301 (bubble magus NAC5.5 clone). Phosban 150 reactor with GFO (experimenting, I've tried seachem matrix carbon, seachem purigen, and seachem phosguard in the past in it). Two little fishies kw300 kalkwasser reactor. Custom ATO with dual float switches from autotopoff.com. And a filter sock. Pumps and lighting are listed below.

 

 

Both tanks have fans running over them. A fan isn't going to lower the temperature 10-15 F below ambient. Remember these are outdoor tanks we're talking about here. The only way to keep them below 80 F year round would be to spend $500 on a chiller. And I don't have that kind of money lying around.

 

[Amphiprion1]

It shouldn't be causing precipitation unless it was warmer than that.

 

So as far as temp goes, if the animals aren't reacting negatively from what you can see, I wouldn't be overly concerned. The only potential downside is that there isn't a lot of margin for error at those temps. That is the upper end of the threshold for many corals, though it sounds as though yours have adapted well enough as many on actual reefs do.

 

These outdoor systems sound rather nice, btw. If you feel like posting, I for one would like to see some pics of them.

[Tamberav]

I already do:

 

 

 

Both tanks have fans running over them. A fan isn't going to lower the temperature 10-15 F below ambient. Remember these are outdoor tanks we're talking about here. The only way to keep them below 80 F year round would be to spend $500 on a chiller. And I don't have that kind of money lying around.

 

Oh yeah, I forgot they were outdoors!!

[NaturalViolence]

These outdoor systems sound rather nice, btw. If you feel like posting, I for one would like to see some pics of them.

 

It's not really in a state to show off right now unfortunately. The patio is a complete mess right now. Equipment/chemicals/etc. in piles everywhere. I've spent days cleaning it up and organizing it. I'm currently in the process of breaking down a swing to make room for the storage racks where I'm going to keep everything from now on. Getting that thing out through the door is going to be a bitch. The electrical work is a complete mess too. Well pretty much everything outside of the tank is a mess.

 

I could save up enough for a used american or new chinese knock-off chiller ($250-300). But in order to avoid buying two I would want to hook the two systems together so that one chiller could cool everything. The problem with this is the whole point of the seperation originally was to keep one system dirty and one system clean. With the pufferfish in the 30 gallon being the poop machine that he is it could make it more challenging to keep the reef tank clean if they were on the same loop. I've done the math and it is feasible to hook all 5 tanks together in one loop with the current elevations. From top to bottom 25 gallon reef -> 18 gallon fuge (80% full) -> 10 gallon sump (65% full) -> 3 gallon waterfall -> 30 gallon fowlr -> pump. 80 gallons total water volume if they were all on one loop. Each is elevated about 1 foot higher than the next in the chain so it would work with proper plumbing.

[NaturalViolence]

These outdoor systems sound rather nice, btw. If you feel like posting, I for one would like to see some pics of them.

I took these tonight (it's the fuge where I currently have most of my frags): http://imgur.com/a/rFMTp

 

And this album is the tank two weeks ago: http://imgur.com/a/ORhl5

 

Unlike you guys I usually don't bother to clean the glass very much. Including before photos. I'm just that lazy. The rocks and sand are spotless though. Although the rocks are green in color so clearly there must be some algae on them. It must be a boring algae or something because there is no apparent film or filaments on it. It just looks like it's been dyed green. You can see some of the precipitation on the glass in one of those shots. For some reason the small amount of film algae I get on the glass is completely ignored by the army of cerith and nerite snails in there.

 

You'll notice I recently upgraded the fuge lights to LEDs (white and blue chinese par20/30/38s off of ebay). I could not be more pleased. They have just the right balance between white and actinic blue to create a strong flourescence from the corals yet without drowning out the other colors. And it gives the water a beautiful light blue color that's very similar to what we get down here in the Caribbean shallows. They're REALLY bright. So far growth seems to be good. I have noticed that they tend to distort the cameras colors big time though unless I film underwater.

 

Edit: Images updated with descriptions.

[NaturalViolence]

Triple post.

 

It just keeps getting weirder. Some days it falls and some days it doesn't. Maybe it somehow has something to do with feeding? I didn't feed anything during that week that I unhooked the skimmer for fear of polluting the water. And now I feed about every other day.

[Amphiprion1]

Fuge looks good! Can't wait to see the corals when they make it out into the tanks. Are they going to be lit with natural sunlight?