Sump Issues


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I feel a little dumb. About a month ago I bought a 72 gallon bowfront tank that was already set up, complete with livestock. I made no changes to it except for getting rid of a few fish and adding the fish and liverock from my 30 gallon tank. Everything has been going well except recently I've noticed an increase in Nitrates (I tested around 10 on Thursday). So after approximately 30 seconds of online research I figured out that the rise in nitrates were likely due to the fact that I have a trickle filter complete with bioballs. It seems that hardly anyone is using bioballs these days because while they are great at colonizing the bacteria that break down ammonia and nitrites, they don't do anything to help the nitrate level because that bacteria is anerobic. The result is that your nitrates usually continue to rise, despite water changes. So I'm in the process of removing approximately 20% of the bioballs each week, and once all the bioballs are removed I'll convert the trickle filter into a true sump.

My question is am I correct in my findings on bioballs and am I going about this conversion in the correct way?

I'd also like to add a couple more questions:
-At what point do you know it's time to change a Poly filter? Does anyone use them continuously or only in emergencys or when water parameters get bad?
-I'm currently running carbon continously under direct flow. How often should I be replacing the carbon (about 6 oz.)? Tricky question, I know. I have a tomato clown, a percula clown, a bicolor angel, a potter's angel, a psuedocromis, and a yellow watchman goby. Also a couple anemones and a few softies. I only feed once per day and not that much imo.

Thanks in advance for any advice and/or opinions!
I believe you are right on in your findings on the bio-balls. I would probably take em all out at once but (read my signature) you may be going about removing them correctly.

I dont use a poly-filter on my reef but that's just my choice, some use them occasionally for water clarity some use em full time. I too run carbon and change minr every couple weeks or so. Some people do it more often. From what I believe, each setup is different and each aquariust a little different in their husbandry
i'd say your correct about bioballs. I used to have them as well but everyone stopped using them and so did I. Now I just have sponges in my sump to help stop Bubbles. I'd say feeding once a day is fine. I don't think that would contribute to the Nitrates. As long as all of the food is getting eaten your fine.
Maroons15 wrote: As long as all of the food is getting eaten your fine.

Yep, instantly. Thanks. I think once the bioballs are out I'll add a refugium (probably seperate) to my sump. I'll ask for help and advice from the ARC members.
Good stuff. Ill be adding a HOB Refugium soon and it will be my first one. I hope it works well.
I read an entire dissertation on the use of carbon the other night and it was enlightening... and boring. I am no expert and I am regurgitating the info that I read, but basically activated carbon loses its "activated" state quickly. Carbon's effectiveness decreases rapidly but then stabilizes until it is finally covered in organic slime. After that it becomes a bacteria breeding ground. Fortunately it takes several weeks for any positive or negative influence from the bacteria build up in carbon. If you leave it in for extended periods of time (months) you might harm your aquarium very slightly, but from my understanding the risk is virtually non-existant. I also read that not all carbons are created equal and few are really good. A common concensous by some chemists were black diamond being good and anything from a coconut was poor. Seems like the "experts" ran carbon for various lengths of time, but most of them now use a cup every 100 or so gallons for about two weeks before changing.