Tony Schall writes...

Dear Bob:

I hope this letter finds you and your family in good health and holiday spirits.

I am attaching some photos taken of my 58 gallon tank. As a person whom has been in the hobby for over 30 years, with over 20 years in the saltwater side of the hobby, the one lesson I learned very early on is that the longer you do this, the more questions you have. I have also learned, and taught (either students, or fellow hobbyists) that the only stupid question is the one not asked. So be patient with me, please.

A little history on my tank:

A 58 gallon Oceanic with a 20 gallon sump. The lighting consists of a power compact unit utilizing 4-96 watt bulbs (2-6700k, 2-700k, bulbs are 8 months old). A Top Fathom 100A skimmer is located in the sump. A Rio 3100 pump returns water from the sump to a Sea Swirl rotating device which uses a 90 degree return pattern. This tank was torn down and set back up 6 weeks ago after a very interesting algae infestation that caused the death of several tangs, crabs,and I believe a few acropora pieces. A sample of the algae is at the local university where a couple of friends of mine are investigating.

When I rebuilt the tank I did it per your specifications from your Live Sand Secrets book (an excellent resource I may add). This is my third attempt a plenum, with my first two attempts using old undergravel plates. My experiences were exactly as you describe in your book. I have been using deep sand beds in my tanks since the late 70's when myself and a couple of friends were breeding clowns in one of my friends basements. We had a lot of help form the local sanitation people who gave us a tremendous amount of information on sand filtration.In return we were doing some graduate school projects for the city.

Parameters for the aquarium so far are running true, except for my calcium level. II am having a difficult time keeping my calcium level above 275ppm. (Tested using a Salifert test kit, a Red Sea kit, a Hagan kit, and the local university lab). MY magnesium level is 1345, in the normal range. I have been using CaribSea aragaMIGHT in my evaporation water (per instructions on the bottle). Interesting is the fact that I can only get a calcium reading of 120 ppm in the evaporation water.

So here are my two questions:

1. It appears that I am going to have to bite the bullet and purchase a calcium reactor. My plans for the tank are to eventually have the majority of corals be acroporas. I will use the soft corals as trade. I have read your review of the Korallin Kalkreaktor and was impressed. My question concerns that reactor vs. a Knop reactor. It appears the Knop unit is around $100.00 less. In your opinion, is there a $100.00 difference in the reactors? I know one shouldn't make a decision based on price, but it definitely has a place in the decision process. Which unit do you prefer? I have heard some negative feedback on the Knop, but it is also been available longer.

2. The second question deals with algae in the tank. As you can see in the pictures, a little bryopsis is appearing. When I set the tank up, I was not able to leave the lights off for the time you recommend in your book. The tank was torn down for over a week before I rebuilt. I wanted to make sure the tank was dry and the previous algae problem was a thing of the past. When the tank was set back up, new rock (I purchased this rock from a gentleman who wanted to get rid of his tank. He says it is Honduran rock. The total weight in my tank is less than 35 lbs. The rock was completely covered with coralline algae (another reason for the low Ca levels), with various macroalgaes present. The coralline is receding somewhat, but I am more worried about the "nuisance" algaes. I did use phosphate remover for the first four weeks per your book, but have stopped using it recently. Currently the phosphate levels and the nitrate (nitrate-nitrogen) levels are undetectable using the test kits I have.

Any suggestions for algae control/ I have not introduced a large amount of snails or crabs as of this letter. I have around 30 astrea snails, with a good local source for more. I am hesitant to introduce crabs as I have no local supplier for good small crabs (red or blue) and have been stung in the past when ordering them. Also, I have seen good coralline growth tanks decimated by some the crabs people were sold as coralline friendly.

Thank you for taking the time to read my letter. I realize that this is the prototypical letter you receive every day, but all hobbyists appreciate your insight.

Tony Schall