[joecon]

I am having major Nitrate problems, resulting in algae growth. All other levels are excellent, other than Nitrate. I do frequent H2O changes and I feed according to specs. I also use RO/DI, but still high Nitrates. I saw this online and am asking for opinions http://www.midwestaquatic.com/sulfur_denitrifier.htm

Thanks!

[Reefland]

Denitrators are not uncommon and are useful, but there are other ways around it. What is your nitrate level at? How large of water changes and how frequently do you perform them on your 75? What is your feeding routine? How many fish do you have and what are they? Protein Skimmer? Other filtration devices?

[joecon]

Nitrates are at 10ppm (whatever that means), I do 25% H2O change every other week, I feed 2 times a day (what they can consume in 3 minutes), 5 fishes (coral beauty, small yellow tang, small maroon clown, medium Indian Yellowtail Angel (aka Cream Angel), and a sand sifter goby). I have 2 CPR Bak Pak 2's (inherited them), an Emperor Bio-wheel filter, and about 90-100 lbs of LR.

Thanks!

[Reefland]

10ppm is not high, in fact it is excellent for a FO system. Here are some suggestions:
Remove the Emperor, it is not needed.
Make sure the skimmer is producing skimmate daily.
Increase to weekly water changes.

[joecon]

Not high? Excellent for an FO system? Cool!!!! That is good to know, I have been under the assumption it has to be zero or the fishes will eventually suffer. The skimmers are very productive, I check them and adjust accordingly daily. As far as the emperor, mechanical filtration is not needed? I hate seeing particulates floating around the tank. Also, why would my LFS suggest me buying it, if it is not needed? I appreciate all the help and for all the suggestions!

Thanks and take care!

[Reefland]

Well, they could be lower but a nitrate of 10ppm will not do any long term harm to your fish. It could be the source of your algae problem and I think you can lower it with some of the suggestions above. Fish can easily live in a tank with that level of nitrate.

You ask why the LFS suggested you buy the Emperor? Well, because you bought it. Mechanical filters like this can be useful for running carbon, but you can get by with the same affect by placing some carbon in a filter bag in a high flow area of your tank. The problem with most of these types of filters is that they do collect a lot of waste and if that isn't cleaned frequently, it will breakdown and cause increased nitrates.