Nitrate

[gandolf]

Say I am having a lot of problems with nitrates, mined are running between 10 and 20 sometimes 50. I have been doing 35 gal water changes a week. and still have nitrates. He is what I have.
90 gal tank
allglass sunp mega 4 w/265 bio balls in it
ETSS Skimmer
Tank is 3 months old w/100 pounds of live rock and 50 pounds live sand
Ammo 0
nitrite 0.05
ph 8.2
sal 1.023
temp 76

 

[Krish]

Welcome to RF! More than likely the thread will be re-directed to the general forum, but in the meantime here are a few thoughts on your nitrate issues

allglass sunp mega 4 w/265 bio balls in it

There's probably your main source of nitrates. Wet/dry's are nitrate factories because they cannot denitrify so you end up with an accumilation of nitrates over time as nitrates are the end product of a wet/dry. Most people will just remove all their bio-balls (a little at a time) and allow their rock to take over full biological and denitrification functions as it can perform then both quite efficiently. Other contributing factors to high nitrates could be not using ro/di water, overfeeding, high bioload etc just to name a few...Do you have livestock in the tank yet?? Just a few thoughts....

 

[gandolf]

I use r/o water no fish just some snails,craps and a star fish

 

[Krish]

Cool... Well, in any event, the bio-balls in your wet/dry I'm almost positive is your problem. We've actually had more than a handful of members here lately with threads dealing with the same issue as you are experiencing now...High nitrates caused by wet/dry's. Bio-balls in a nut shell have no anaerobic zones which is what is required for de-nitrifying bacteria to grow and perform the function of converting nitrates into nitrogen gas (denitrification). Bio-balls however sit in a highly oxygenated environment with tons of surface area for nitrifying bacteria to grow which are those that are responsible for converting ammonia into nitrite and then into nitrate in a short amount of time, which is does very very effectively. That is why after a water change, your nitrates will shoot right back up in a short time. The wet/dry is so efficient at what it does, that nitrates are constantly being produced as waste is being broken down. You ditch the bio-balls (again removing them slowly over time so as to not shock your biological system) and allow your rock to do the work for you and you'll be well on your way.

 

[gandolf]

Waht king of filter do you recomend for my 90 gal

 

[Krish]

Your live rock is your filter It holds all the necessary bacteria to perform all of your biological functions including denitrification. The rock is working for you now, but having the wet/dry hooked up as a wet/dry with bio-balls, kinda gives the live rock "a run for its money" as it is can produce nitrates a lot quicker than the live rock can work them off. By removing the bio-balls and allowing the tank to stabilize where the live rock takes over full responsibilty of "filtration", as nitrates are produced, the live rock will be able to work them off. Also, good husbandry (water changes) protein skimming, using a macro algae in a refugium can all aid in keeping nitrates down. Where your wet/dry is concerned, you can just convert your wet/dry and still use it as a sump. I actually did that to a wet/dry I had because I had tons of nitrate issues. After getting rid of the bio-balls and making a few other changes, I haven't seen nitrates since about last year May. I'll fetch you a few pics of how I converted my wet/dry on my old 75gal incase it may give you some ideas just give me a few...

 

[Meche]

Your live rock and skimmer are good enough. Some people also run carbon.

 

[Krish]

Here's how I converted a wet/dry I had custom built into a sump with a refugium section...This is just of example of what can be done


It started out like this...







I then added in some baffles so that the bio-ball chamber could fill with water to add volume and also, so I could keep a macro algae in there if I wanted to (which I never did ) If you look closely behing the brace for the stand, you could see the light sitting over that center chamber





And lastly, I wanted a bit more volume added to my system, so I expanded my sump and added in another chamber.

 

[chris&barb]

I use r/o water no fish just some snails,craps and a star fish

craps in you tank can definitely cause high nitrates J/K

Krish is giving great advise

 

[Krish]

craps in you tank can definitely cause high nitrates J/K

ROFL!!! They're our worst nightmare