Wet & Dry Filter - How does it work ???

[topgundcp]

I am new in this hobby and just set up my salt water tank(fish only) for about 3 months. My tank set up is as follows:
- 70 gallon tank
- 75 lbs LR
- 80 lbs Live sand
- wet and dry filter
- 210 Watt lighting (50/50)
- 2 damsels
- 2 angels ( a flame and a 3-spot)
- 1 Blue tang
- 3 wrasses ( 2 small and 1 large)
- 1 small yellow tang
- 2 clown fishes
- 1 blenny

Every time I test the water with Salt Water Master liquid test kit
, the result is:
Ammonia = 0
Nitrite = .25
Nitrate = between 20 and 40 since the color are so close I cant
hardly tell

I did make partial water change 3, 4 times ( 15-20 gallons each time) then test the water again next day, the result still the same.

I thought that by making partial water change, the Nitrite and Nitrate levels should be improved but did not.

My question is: I don't know how the Wet and Dry filter works, I read one of the forum and it says the bio balls are Nitrate factory so should I rinse out the bio balls ??? Also, I heard that the water in the sump underneath the bio balls should not be taken out since the benificial bacteria live there,
is it true ???

Please advise.

 

[loganj]

The bacteria that live on the bio balls are aerobic bacteria. They thrive in the oxygen rich environment that the wet/dry filter offers. They also convert ammonia/nitrite to nitrates almost immediately. Normally I would say jerk the bio balls out and let the LR take care of the bio filtration, but since you have a high fish load, I don't know that it would be a good idea. IMO, you need at least another 40 lbs of LR. Then you might start removing the bio balls a few at a time and keep a check on the ammonia/nitrite levels. Since your tank is only 3 months old, I expect the trace nitrite levels are due to the high bio load. I think they will eventually come down to 0. As far as taking out the water in the sump...this water is in constant motion...being pumped up to the tank and flowing back down. I don't think it will matter where you take water out.
Logan J

 

[fishfreek]

Cut back on feeding to once a day and dont feed extra that one time a day to make up for putting less food in the tank.

That should help with your nitrite also.

I second everything logan said.

 

[topgundcp]

Thank You LoganJ and FishFreak.

I have been feeding them 2, 3 times a day and yes, I will cut back to once a day.

Another thing I forgot to ask is: My tank was completely cycled at one point ie. Ammonia=0, Nitrite=0, Nitrate=0 then my Blue Tang got cloudy eyes and ich. I was advised by LFS owner who is a Biogolist to soak Ampicillin with food and feed them in my main tank and it was cured and also prevent the rest from getting the desease. Even though the instruction for AMPICILLEX says it will not affect the biological filter beds
but since I read everywhere they say Antibiotic will kill the Benificial Bacteria and in turn it will mess up your Biological Filter beds. I am a little confused to which one is true ???

Please Advise.

 

[loganj]

Yes, antibiotics will hurt the bio filter. Some more than others I'm sure. Since ich is a parasite, I wouldn't have thought that any antibiotic would be effective against it.
Logan J

 

[topgundcp]

My Blue Tang also got cloudy Eyes and I guess Ampicillin cured that. For some reason the ich also went away.