ARC Reef Coralline Algae in a Bottle - Purple Helix, Live Spores and Nitrifying Bacteria for Saltwater Reef Tanks, Seeds Dry Rock with Vibrant Purple Coralline, Treats Up to 50 Gallons, Brush Included

This is a great product for helping seed a reef tank with real coralline algae spores. I like that it is not just a basic calcium or magnesium additive, but actually contains live coralline algae spores designed to help establish that natural purple reef look over time. I used it for my new saltwater reef tank rockwork, and it worked just as well as when I used it in the past for a tank that refused to grow coralline and was shocked to actually see coralline show up a month or 2 later, that tank literally had no growth before that and it was set up for a few years, so definitely a believer in this stuff and will use it on all future tanks. Like anything living in an aquarium, it still takes time. Stable alkalinity, calcium, magnesium, lighting, and overall tank conditions still matter. But as a seeding product, this is an amazing coralline algae starter to speed up that long process. Overall, I am very happy with it. It is easy to use, reef-specific, and much more appealing than relying only on random hitchhikers or waiting forever for coralline to spread naturally.

Great Coraline algae starter! Works great and customer service is amazing. Would recommend to a friend!

I have a very good reef. I have been doing this for over 17 years, am a chemist, and have worked in the industry. I thought this would be a great product to try as all my parameters have been perfect I just didn’t have any corraline. This product did not work. At all. I contacted the manufacturer 8 weeks in and they told me I hadn’t waited long enough (fair enough) but now it’s been 4 months and there isn’t a spot of coralline. I contacted the manufacturer twice now after and have gotten no response and they won’t refund my money. BUYER BEWARE

Worked great, i saw results by the 2 month mark. It started with little spots all over. My tank is well established and rock stable but only now was i finally able to get coralline growth. The colors are very vibrant also, not muted like tanks ive had in the past. I am super happy with these results.

40 years aquarium experience here. Never took off for me. Water parameters were perfect as well as temperatures. Just now getting coraline that lost likely occurred from snails I put in there. It’s been months since I treated with the product. I may try it once more with another freshly cycled tank but will probably just add a bunch of snails with coraline already on them.

I purchased the purple and pink bottle. I also used Carab Sea Purple Up in Tandem. The product came with detail instructions which I followed to a T. It has been about a month and I am starting to see pink coralline develop in my tank. I think the product has some influence with that as well as my addition of high calcium and aragonite. This is a product that may give different results depending on the user, tank size, parameters, etc. Corelline does show up with a mature tank and stable parameters. This product is more of that beneficial kick start in tandem with positive bacteria for the tank. So has it worked? Yes. Be patient and be aware different users may get varying results. Allow 30-90 days for results. The nitrifying bacteria in the bottle is also that feel good for tank growth. I think any new tank less than a year old could benefit from the use of this product.

I’ve added zero means of getting coralline to the tank, other than this. A few weeks later… I’ll be scraping the glass for all of eternity! There are 1/4” sized purplish spots everywhere on the glass. I can only assume it’s started all over the rocks as well. I really recommend this if you’re trying to keep foreign pest out of your tank, like me. I avoid live rock and the like… like they’re the plague. I don’t have any snails or hermits with coralline on their shells. This seemed like the safest option for me to get the spores flowing, and it didn’t disappoint. Read the instructions and don’t blame the product for your poor water quality! Your dKH, Calcium, Magnesium, etc is super important… all of that has to be on point to grow coralline, and without good parameters this bottle isn’t a miracle fix. Fix your water before buying this! dKH - Higher than 8. Mine is consistently at 9.3-9.6 Calcium- Right around the 400 area. Mine stays around 400, +/- 20 Mag. - Mine hovers in the 1100 range. I may be a tad low, honestly. I’d like 1300, but this seems to like 1100 just fine. Stability… Stability… Stability…

It definitely works. Within weeks I had purple pinkish spots start developing on the glass and frag plugs.

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