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Just ordered the Osmolator 3155 and Calcium Dispenser 5074 from Marine Depot for a 90g with a 12g sump. Calcium requirements arenââ"šÂ¬Ã¢"žÂ¢t too high right now so I think it should be enough. Plan is to add a lot of SPS so Iââ"šÂ¬Ã¢"žÂ¢ll likely dose with a 2 part to supplement calcium and alk levels.

Can you use a bigger reservoir? E.g. 20g? Will the calcium dispenser only add the amount of Kalk based on the 7 gallon reservoir? Sometimes we go on long trips and canââ"šÂ¬Ã¢"žÂ¢t necessarily rely on the person taking care of the tank to refill the reservoir.

Where can I get manuals for the osmolator and dispenser? If I enter the numbers into the Search Phrase box, it simply takes me back to the product info page, not a link to a pdf manual.

Looks like this is a great system for auto top off as well as Kalk supplementation. Thank you!

If you enter 5074 or 3155 in search you will get the option to view "Instructions for use", if you cannot get this to work i can email a PDF if you send me an email. The reactor should not be used with more than 4 tsp of Kalk so 20 agllons would depleat this amount of kalk about halfway through, the unit would function but the last 10 gallons will be just water. Careful with the 2 part additives, in combination with kalk they can be potent sources of precipitate. I would try a gluconate based product like those offered by Seachem.
Thanks, I can't get the manuals, when I enter in the numbers, I don't get any links to manuals. I've sent an e-mail requesting them by e-mail.

Also, gluconate and precipitate are new words to me. So many new words in this hobby! I've read a lot of posts with people stating they dose kalk and use a two-part. What is precipate and what is the problem I'm concerned about? Also, what is a gluconate based product? One of the liquid CA supplements? E.g. Turbo Calcium by Kent, Reef Calcium by SeaChem? If the supplement you're talking about is only concerned with Calcium, how would you suggest maintaining alkalinity?

Thanks!! Really excited to get your product. Your presence on RC made it a much easier decision.

With respect to gluconate based calcium additives, watch for signs of nuissance algae. It's been reported that gluconate-based additives can cause algae outbreaks.

A "precipitate" is what occurs when two ions form a salt that is insoluble in water. Calcium ion and carbonate ion, for instance, combine to form calcium carbonate, which is a solid and can't dissolve easily in water that has a pH of what we keep our reef tanks at. If you add your carbonate additive when you drip Kalkwasser, the pH of your tank can rise to the point where calcium carbonate has a very hard time staying in solution, and it'll precipitate out of solution. This is noticeable if your tank becomes cloudy for long periods of time, or if your sand bed starts to cement together.
Just to confirm, a gluconate based additive is one of the liquid calcium supplements like Turbo Calcium by Kent, Reef Calcium by SeaChem? I've been using Salifert's liquid CA as my only CA supplement (which could explain my recent Cyano outbreak :>).

I have a PH monitor so, if I use a two part, watch my PH and test CA and Alk levels, I should be fine. Right? If I understand you correctly, if the PH is where it should be, then precipatate should not be a problem.


The problem is Kalk raises pH and Alkalinity, you use a two part additive basically one bottle of Calcium Chloride and one bottle of Sodium Carbonate/Bicarbonate and you get problems with precipitation of calcium carbonate. Most novices don't test and add calcium half hazardly, big mistake always test before you add. Turbo Calcium is Calcium Chloride, Calcium Gluconate is used by Seachem and no other company that I know of. Gluconate is essentially sugar and yes it can feed algae but this is the lesser of two evils in my opinion. The ionic imbalance that two part additive can cause and the excessive formation of precipitates leads me to use them only as a last resort. In an ideal world of course everyone uses kalkwasser and a calcium reactor but besides that all additive must be used sparingly and only when a test result indicates they are needed not according to some voodoo formula add twice a week nonsense. I would suspect Saliferts product is Calcium Chloride but you can always ask in the Reef Chemistry forum and Salifert is a good company with a good reputation. It is not that two part products aren't good they all have their draw backs, it just seems these products cause more problems with continued use than others especially for newbies. In the long run I have seen many tanks dosed with these products have unusual shifts in chemistry after a couple of years and excessive formation of lime (precipitate product) on pumps and heaters. These problems can largely be averted by testing and wise sparing use of additives- and that means all additives.
So you would suggest using Kalk to maintain CA and Alk and using the Seachem Calcium Gluconate ("Reef Calcium"?) to supplement CA levels if necessary?

I had not read that Kalk also increases Alkalinity. So by using Kalk, you no longer have a need for a buffer like Kent's SuperBuffer (which I've been using with the Salifert CA)? Presently, my tank is not using a whole lot of CA but does seem to go through MG and alkalinity pretty fast.

I am a newbie but am also learning rapidly and testing everything. I have a PH monitor, refractometer, and 7 of the Salifert tests. Definitely past the point of dosing per week rather than when needed. I'm just seeking the best way of maintaing CA and Alkalinity because, to my understanding, that's basically all you need to do. You should get the other trace elements via regular water changes with RO/DI water and a good salt.

I realize this isn't exactly the right forum for this discussion but since I'm going to use your product to dose Kalk, I'm also seriously appreciating your knowledge on the related issues. :)

Back to my previous question: If I use the 20g reservoir, can I simply add another 4 teaspoons of Kalk once per week? I would then get 7 days out of the Kalk but 2.5 weeks from the reservoir. When I'm gone for more than 7 days, the person taking care of the tank could just add more Kalk and not worry about the water.

Thanks for the manuals.

If you follow the directions in the Calcium Dispenser you will see different recomendations for different size aquariums and their inhabitants. The amount of kalk the dispenser uses is regulated to some extent by the water passing through it. It mixes a saturated solution, basically water can only hold so much of anything and kalkwasser is weakly soluble in water. One problem with traditional dispensing of kalk is it reacts with air to form Calcium Carbonate and precipitates so you have an even weaker solution. The dispenser seals the mixture from the air and provides sufficient reaction for a saturated solution to develop. This solution however will not have enough calcium on its own to maintain all your needs. Kalkwasser is a week calcium supplement. Calcium Gluconate I believe is the strongest followed closely by Calcium Chloride. Kalkwasser is a buffer in two ways. First, your buffer is largely depleted by organics decomposing and forming organic acid which the buffer binds to. Kalkwasser or Ca(OH)2 works as a buffer as hydroxides can directly bind and precipitate some organics and preserve existing carbonates and in addition the hydroxides react with CO2 in the water to produces bicarbonates. On its own it may not be sufficient, this will depend on evaporation rate and load so you will want to keep some buffer on hand but it will reduce the need. You said your aquarium was 90gals. What type of flow do you have? Do you have sufficient surface agitation? I only ask because you mentioned slime algae and using a lot of buffer and magnesium. A low pH and slime algae can be symptomatic of low flow. Target 10-15* an hour turn over. Make sure all pumps are clean and running optimally and good surface movement is present
Tank is 90g overflowing to a built in surface overflow box in the center of tank by gravity to a 12g sump with mud/caluerpa. My flow was low and I had a bad outbreak of slime. I replaced the return pump, added two sea swirls, and dramatically increased the flow. The slime is about 15% of what is was and continues to reduce. I now have a micro-bubble problem from all the flow but I have a plan for that and is a topic for another forum. :)

Nitrates are 15ppm, 0 Ammonia, 0 nitrites, 0 phosphates. Haven't figured out why the nitrates are at 15 but I suspect its the bioballs of the ecosystem sump.

PH varies from 8.0 in the morning to 8.3 during light cycle.

So I'll probably still need a CA supplement and may need buffer. Seems that your recommendation would be to use CA gluconate for the CA and perhaps continue using the Kent Superbuffer? But of course, only when needed.

Can I simply add the additional kalk to the dispenser in a 20g reservoir as I mentioned in my previous post?

Thanks Roger, really appreciate the help and the education!!

Yes, you can add kalk as you wish, just play with the system for a while, see how long it takes to use up what you add and follow the directions regarding shaking it and making sure the system is topped off before adding fresh powder. Not doing this can blow strong kalk powder directly into the tank.