jlinzmaier
Premium Member
I've been battling this silly problem for about two years now. If/when I try to raise my alk past 6.5 dkh I seem to seriously irritate my SPS. I get a definitive lack of polyp extension followed by STN throughout areas of the entire corals tissue (not just the base or the tips - tissue begins to recess at all areas of the corals skeleton). My tanks chemistry is very stable except for when I try to adjust alk up or down.
It just makes absolutely no sense to me. I can change absolutely nothing for weeks and things will be fine (with the exception of what I think is relatively slow SPS growth and all but a complete lack of corraline algae growth). As soon as I try increasing the alk level I get complete lack of polyp ext (day and night) and many sps (monti's, acro's, and stylo's) start to develop STN at various areas (base, tips, and throughout the body of the coral). The more I raise the alk the more tissue loss develops and the faster it occurs.
I always make any adjustments very slowly (never more than 0.5 dkh spaced over a 24 hr period and never more than a 1dkh shift in a week. I've tried raising alk by dosing a bit more kalk over several weeks time and still had trouble. I thought maybe the increase in pH was irritating the corals. I then backed it down let the tank recover for about 2 months then I tried raising alk by increasing my ca reactor effluent rate. Once I hit 7 or higher it all goes downhill. I also tried raising alk with soda ash from BRS and got the same effect.
I don't do any carbon source dosing. My ca is stable at 400 and I realize that dosing more kalk or increasing the ca reactor effluent rate will increase ca but not enough to make a detrimental impact of any sort. My mag is always stable at 1300.
I just don't get it. I can tell if my alk is drifting above 6.5dkh because the lack of polyp ext in my monti verrucosa is the first noticed.
Any thoughts on why this would happen?? I have really slow growth in my SPS and many corals haven't grown more than a cm or two over the past 2 years. I also have little to no corraline algae growth and I'm sure they are both related to low alk levels.
I have tested my ELOS kits against two different control solutions from different manufacturers and the kit always read the solution as it's labeled. I've tested with Salifert and get a reading about 1-1.5 dkh higher.
I do notice I seem to get a fair amount of sand clumping in the areas of highest flow. I'm assuming that would be caco3 precipitation because some of the chunks turn completely rock hard. I even had some caco3 precipitation onto my chaeto a few weeks ago????? This seems odd to me that it would occur at alk levels of 6.5-7 dkh. I've never gotten the alk past 7.5 dkh because the corals begin to look so stressed I'm afraid I might kill them if I continue on.
I dose the ca reactor effluent and kalk into my sump (at opposite ends) and it is always mixed into the water nicely before it returns to the display. I dose kalk constantly throughout the day as well as using my ca reactor to keep up with what my kalk can't (don't have a lot of evaporation).
What's completely baffling and very frustrating is that many friends have gotten frags from me and they maintain their alk levels at 9 or 10 dkh and the corals they get from me thrive. In their tanks the corals grow at what I would consider normal or fast and they have spectacular polyp extension.
I can even see coral irritation and lack of polyp extension when I do a small water change with a salt mix like IO or RC which has a high alk level.
Any thoughts would be greatly appreciated!!!
Does anyone else have trouble like this??
I'm almost to the point of having my water sent off to ENC labs to have a full analysis to see if some heavy metals are out of wack and precipitating out onto the corals surface when alk levels rise. That's the only "shot in the dark" guess that I can come up with at this point.
Jeremy
It just makes absolutely no sense to me. I can change absolutely nothing for weeks and things will be fine (with the exception of what I think is relatively slow SPS growth and all but a complete lack of corraline algae growth). As soon as I try increasing the alk level I get complete lack of polyp ext (day and night) and many sps (monti's, acro's, and stylo's) start to develop STN at various areas (base, tips, and throughout the body of the coral). The more I raise the alk the more tissue loss develops and the faster it occurs.
I always make any adjustments very slowly (never more than 0.5 dkh spaced over a 24 hr period and never more than a 1dkh shift in a week. I've tried raising alk by dosing a bit more kalk over several weeks time and still had trouble. I thought maybe the increase in pH was irritating the corals. I then backed it down let the tank recover for about 2 months then I tried raising alk by increasing my ca reactor effluent rate. Once I hit 7 or higher it all goes downhill. I also tried raising alk with soda ash from BRS and got the same effect.
I don't do any carbon source dosing. My ca is stable at 400 and I realize that dosing more kalk or increasing the ca reactor effluent rate will increase ca but not enough to make a detrimental impact of any sort. My mag is always stable at 1300.
I just don't get it. I can tell if my alk is drifting above 6.5dkh because the lack of polyp ext in my monti verrucosa is the first noticed.
Any thoughts on why this would happen?? I have really slow growth in my SPS and many corals haven't grown more than a cm or two over the past 2 years. I also have little to no corraline algae growth and I'm sure they are both related to low alk levels.
I have tested my ELOS kits against two different control solutions from different manufacturers and the kit always read the solution as it's labeled. I've tested with Salifert and get a reading about 1-1.5 dkh higher.
I do notice I seem to get a fair amount of sand clumping in the areas of highest flow. I'm assuming that would be caco3 precipitation because some of the chunks turn completely rock hard. I even had some caco3 precipitation onto my chaeto a few weeks ago????? This seems odd to me that it would occur at alk levels of 6.5-7 dkh. I've never gotten the alk past 7.5 dkh because the corals begin to look so stressed I'm afraid I might kill them if I continue on.
I dose the ca reactor effluent and kalk into my sump (at opposite ends) and it is always mixed into the water nicely before it returns to the display. I dose kalk constantly throughout the day as well as using my ca reactor to keep up with what my kalk can't (don't have a lot of evaporation).
What's completely baffling and very frustrating is that many friends have gotten frags from me and they maintain their alk levels at 9 or 10 dkh and the corals they get from me thrive. In their tanks the corals grow at what I would consider normal or fast and they have spectacular polyp extension.
I can even see coral irritation and lack of polyp extension when I do a small water change with a salt mix like IO or RC which has a high alk level.
Any thoughts would be greatly appreciated!!!
Does anyone else have trouble like this??
I'm almost to the point of having my water sent off to ENC labs to have a full analysis to see if some heavy metals are out of wack and precipitating out onto the corals surface when alk levels rise. That's the only "shot in the dark" guess that I can come up with at this point.
Jeremy
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