To Bio ball or not to Bio ball that is my question

[clownin around]

I have a 58 Gal Oceanic tank. Sealife Inc Power compacts for lighting. Sealife Systems Pro 200 sump w/ protein skimmer.. will include picture. the sump is under cabinet. I have 85lbs of live rock and a 2" live sand bed.
My residents are a pair of very tiny false perc clowns, one yellow tang, one lawnmower blenny, one coral banded shrimp, one sand sifting sea star one baby horse shoe crab, and 12 snails of various parentage, and one star polyp coral. I can not get my nitrates lower then 10 despite weekly water changes. From what I have read this may be the fault of the bio balls. My tank has been up and running successfully for three months now but recently I have noticed a decline in my one and only coral a star polyp coral where before it was flourishing. I tested my nitrates for a period of two weeks through my weekly five gal water change and didnt notice a drop in my nitrates. So I am wondering if a deep sand bed or refugium instead of the bio balls would decrease my nitrates. How would I change this over under the cabinet? Do you need a light for a deep sand bed or would it be fine under there? Or should I just be changing more water? TIA

 

[ReefLady]

IMO, if you have 85lbs of LR, you could definitely do without the bioballs.

I can not get my nitrates lower then 10 despite weekly water changes. From what I have read this may be the fault of the bio balls.

Likely so, though 10ppm really isn't all that bad.

recently I have noticed a decline in my one and only coral a star polyp coral where before it was flourishing.

I seriously doubt this has to do with the nitrate readings. Calcium & alk levels? Water flow? Try blowing them off with a turkey baster - they can become 'unhappy' if they accumulate detritus on them. Also salinity & temp?

So I am wondering if a deep sand bed or refugium instead of the bio balls would decrease my nitrates.

Both are beneficial and effective at reducing nitrates - a DSB by the denitrification process, and a refugium by nutrient uptake (via macro). If you want a DSB, you'll need to find a new home for the sand sifting star and horseshoe crabs though, both are predators of sandbed fauna, and will keep any sandbed from being "live".

Do you need a light for a deep sand bed

No, but for a refugium you would.

Or should I just be changing more water?

5g weekly should be sufficient, but you may need to do a few larger water changes to get rid of the nitrates. This may be ineffective, until you get rid of the bioballs.

IMO, I would start by slowly removing the bioballs (1/4 per week for 4 weeks), do weekly 15%-20% water changes during this time. At the end of 4-6 weeks, reevaluate.

HTH,

 

[clownin around]

thanks so much for all the info. all other water parameters are great sal temp alk and calc check out ok by my salifert test kits. Will do a large water change and see if that helps out the coral perhaps a snail perished that I cant see either way the large water change should rectify things in that department get the nitrates back down. great idea about the turkey baster I will try that as well I was thinking of doing the deep sand bed in the sump once the bio balls are gone, not in the main tank so do I still have to get rid of the starfish and the horse shoe crab if I do it there? I would not have purchased these if I had known better at the time though they do keep my sand very very clean and pretty.

 

[ReefLady]

I was thinking of doing the deep sand bed in the sump once the bio balls are gone, not in the main tank so do I still have to get rid of the starfish and the horse shoe crab if I do it there?

No, as long as the sand bed is remote, they won't adversely impact it. Sorry it missed that first time around. 8)

 

[clownin around]

Dont worry about it lol thanks for the feedback! and you were very right about the decline of the coral not being the nitrates. i tested for nitrites and amonia which I hadnt done in a while scince it had been 0 for so long and low and behold they were there in low concentrations but that they were there at all was concern enough I tested and retested still there I was scratching my head big time. then i thought I would srub the protien skimmer change filter pads even though it wasnt time to do so. Low and behold my protien skimmer wasnt skimming !! well well well did I feel silly.. just shows how easy it is to become complacent with all our automation. I fixed it and will do 20 % water changes every other day till things are rectified. Thought I would share my experiance and thanks reeflady for your heads up! I could have had a bigger problem then I do now if you hadnt prompted me to dig deeper. =)