The infamous salt discussion... REVIVED

[+boognish]

Preface: My 75 gallon mixed reef had been set up for 5 or 6 years with a deep sand bed. For the last 2.5 yrs it was on 'self-maintenance' mode with very few water changes and several different types of algae (both good and bad) set in. I used Tropic Marin Pro salt when I did do changes. I finally got the time to get back into daily maintenance, hooked up my calcium reactor, did weekly changes and dosed Kent Tech-m, and started dosing Brightwell's Microbacter-7, bio-fuel, and coral-amino. The algae all but disappeared, but I was not seeing any drastic changes in coral growth (except the lack of growth of xenia which is good...). I switched salt to the Tropic Marin Bio-Actif and saw incredible color and changes within a couple weeks. I started building a new tank and had to move my 75 to another room, so I got rid of the deep sand bed during the move and things got even better. ALL algae issues disappeared.

Things went great for about 8 months, and now the algae started coming back. Some very hardy sps I have had for a very long time has recently stopped extending it's polyps, stopped growing, and losing some color. Several sps frags I recently purchased that were growing and extending nicely stopped growing and some died (rtn) over night. I have not been running my calc reactor because the regulator broke, so I have not been testing calc or magnesium - assuming the calc should be dropping. My phosphates are not showing up on any test I use, so assuming I MUST be not testing with good kits or incorrectly since algae needs phosphates, I had it tested by Bruce at Aquatek with his ridiculously expensive Tunze kit. He also tested very low: .001. On a whim, I tested magnesium.... off the chart... Assuming it was because my calcium was low and not using the magnesium, I got a new regulator and hooked the calc reactor back up. I tested my calcium to get the baseline before cranking it up... IT'S AT 560! How could it be so high when I haven't had a reactor hooked up for over 6 months?!! And why aren't my sps not growing with such a high level of Ca? Lastly... where is that Ca. coming from? Today, I tested my Tropic Marin Bio-Actif mix and the calcium was 560, magnesium was 1200(ish). I am also trying to figure out where the extra magnesium is coming from since my tank is MUCH higher than the freshly mixed saltwater.

I am leaning towards the Bio-Actif salt as the source of my chemistry confusion. They don't tell us what is in it... just that it's good stuff that your coral needs... Thinking I needed to do more frequent water changes to get rid of phosphates that I couldn't find in testing, I've been steadily increasing my Ca and Mg on a weekly basis.

I know a few in this forum have used Bio-Actif for a while. Are you still using it? Have you seen any issues after using it for a long time? Unless someone can identify anything else that I may be doing wrong, I am going back to Tropic Marin Pro or another salt for a while to see if things balance out. What salts do you use? Is it ok to alternate salts? If it is ok to alternate salt mixes, it seems ideal so as to not end up where I am.

Any advice, input, criticism, blatant insults, etc greatly appreciated!

[+mcallahan]

What has your Alk been this whole time? If your Ca reactor has been offline, your sad and dying SPS could be due to daily ALK swings.

Your phosphates are probably 0 as the algae is binding all the phosphates they can find. Doing frequent water changes won't put a dent in your phosphate levels as it takes large water changes to drop phosphate levels significantly. Will your tank be happier w/frequent changes (esp. considering the bioactif instructions call for it?)...very likely.

And your line about your Mg being off the chart b/c, "Assuming it was because my calcium was low and not using the magnesium," not sure what you mean there...

I've been using the bioactif for 8ish months (I think, can't quite remember when I started) and I did see some slight color changes, but not a lot. Keep in mind I've been carbon dosing my tank for 2 years now so I didn't expect a big bang from the bioactif as my tank was already in a low nutrient environment.

From the reading i've done, the bioactif is like carbon dosing which would help explain your explosion in color since your tank probably went to ULNS.

All that being said, I'd say your high Mg and high Ca could be due to the fact that your corals aren't growing much (you said they weren't happy) so Ca and Mg aren't being taken up.

Finally, high Ca doesn't = SPS growth. There is a myraid of factors that all go into SPS growth.

[+boognish]

Thanks for the response, Mark.

When I ran my Calc reactor before, the kH was a steady 13/14. When it was down (up until yesterday), I used CoralBuilder in my top-off and it was around 7 or 8 each time I tested. I didn't test too frequently. I know that is low, but not dangerous and I didn't notice a swing in kH or ph other than a diurnal ph swing from 8.4 to 8.1. kH is slowly increasing since I have the reactor hooked back up. It has only been 1.5 days.

My understanding of the relationship between magnesium and calcium was a little off. It isn't 'used up' by the calcium, after all. This article I just read helped me out quite a bit:

http://reefkeeping.com/issues/2006-06/rhf/index.php

Have you tested your saltwater mix before adding to the tank? I am surprised by the high ca level in mine. If you get a chance to, I'm curious. I did not get the same reading last year on my first bucket, so I am wondering if they differ that greatly from batch to batch or if I should mix this one up.

[Mike M.]

I'm going to cut to the chase on all this. You cannot water change your way out of a nitrate or phosphate problem. There, I drew a line in the sand. In addition, you can reduce those levels too quickly and cause STN to begin in your stoneys so don't get in a hurry(i.e. a huge load of GFO)

I suggest a slow approach. Take weeks or month or two to begin reducing your nutrient levels via use of the BioActiv Salt you mentioned which I do believe is a good product and then using a carbon source... I would suggest ZeoStart3 and Zeo Bak. Dosing 3 drops of Zeo Bak three times a week and 1mL ZeoStart 3 daily and you will get the problem under control in an ordered fashion. Pick your alk point and run it there. If 10 is your bag, then 10 it is, but if you do dose bacteria and carbon, you'll find your tank will run near seven.

Get a Hanna Checker and monitor phosphate. When you get between .02-0.04, reduce your carbon dosing by 50% so as not to over reduce the tank. At that point, everything should be looking super. 5 gallon weekly water changes for your tank at the most. Don't rock the boat with water changes. They are overrated in my mind.

Run your magnesium at 1300 and calcium 380-420. Higher isn't better like Mark said.

Skim, skim, skim.

This ought to fix you up!

[+mcallahan]

I'm going to cut to the chase on all this. You cannot water change your way out of a nitrate or phosphate problem.

I couldn't have said it better so thanks Mike!

Reminds me of another great saying, "You can't save your way to success"

[mhart032]

I'm going to cut to the chase on all this. You cannot water change your way out of a nitrate or phosphate problem.

I couldn't have said it better so thanks Mike!

Reminds me of another great saying, "You can't save your way to success"

i agree completely, water changes are over rated, and ive seen bad bad ugly tanks full of gha get awesome sps growth. then like both these guys mark and mike have super nice tanks and get fantastic growth as well. so its hit or miss. as far as "you cant save your way to success" ive learned the hard way that is so true. i think i actually spent more on garbage for my tank then the rite stuff to begin with. i learned this on the new build. buy the best to begin with and it will save you down the road.

[+boognish]

Bringing this one back to life with some answers and results...

I still have a couple low-flow areas with a little algae. The algae is maroon in color and as I said, only in areas with low flow. It is not 'taking over', so hasn't been that much of a concern, just an annoyance. My main concern was the lack of color, growth, rtn on a couple sps, and dissolving completely of a couple zoas - tubbs blue mainly . I am pretty sure that all the coral issues were caused by the high magnesium and ca, and I finally put 2 + 2 together and found the root of the problem.... Salinity... I had been using the same hydrometer for a few years. Although I rinsed it every time with RO/DI, it's reading was incorrect. I borrowed a friends refractometer and discovered I was actually around 1.033-ish when I thought I was exactly 1.026. duh... high concentration of mg and ca from a salt that, when mixed correctly, has these at optimum levels, points to high salinity. So, with my weekly water changes to try to fix the algae issue, I was steadily increasing my salinity and mg to dangerous levels. So I now own a refractometer and have gradually reduced salinity by removing saltwater and allowing it to be replaced with top-off for a bout a week. I'm at 1.026, now and I'm seeing some nice color coming back to my Cali Tort, polyps are extending more during the day on all sps, and my zoas seem to be a bit more 'full'. Ca is about 440 (was 550), Mg is 1400 (was 1750+). It has only been a few days at 1.026, so I am hoping to see more positive results over the next couple weeks. I'll resume my microbacter7, bio-fuel, and coral-amino schedule tonight.

My plan for the algae is to remove the rocks with algae (most have no coral or just GSP) and scrub it off with a wire brush. I've added 5 large mexican turbo snails, but so far, they haven't found the problem areas or are daunted by the workload. They have done a great job getting the glass and other areas as well as a bang-up re-arranging of most everything else in the tank, though.