Help! I can't get nitrates down

[inawe]

:help: To start, I have a 39g, about 40-45lbs. LR, 40lbs. sand, a Filstar xP1 canister filter, powerhead, Visi jet skimmer, 2 cleaner shrimp, 2 strawberry crabs, several little hermits, 4 snails, and a pajama cardinal. I do water changes every 3 weeks with RO saltwater I buy at the LFS. My prams look like this...
SG - 1.023
Ammonia - 0
pH - 8.2
Nitrites - 0
Nitrates - 20
Water change will bring the nitrates down, but only temporarily, then they go right back up.

Although the canister filter was just added a couple of weeks ago, changed from eclipse biowheel, I was having the same trouble before the change. I feed daily with frozen food. Everybody eats and leaves no crumbs. I've been giving small pieces of the sheet seaweed, which the crabs, hermits, and shrimp really love, about every 3 days. And again, they seemingly eat it all, if that makes any difference.
What am I doing...or not doing? What do I need to do...or not do? I would really like to add 2 - 3 more fish and some coral, but can't until this is resolved.
Help???

 

[sepulatian]

How long has this system been running? What kind of frozen food are you feeding and how much at a time?

 

[inawe]

The tank has been up for about 5 months now. The food is Saltwater Multi-Pack. There are 4 different kinds of cubes...marine cuisine, emerald entree, omega-3 brine shrimp, squid. I feed about one-forth of a cube each day.
don't know that this makes much difference, but the little bitty feather dusters come out of the rock to feed, and last night I discovered a couple of hitch hikers...a gorilla crab :scared:, and what I think may be a teeny starfish...all I could see were 3-4 little bitty red/white striped legs sneaking out of a piece of rock. Still trying to catch that ugly crab...kinda like a tarantula!

 

[badoleross]

A canister fitler can be just as bad as the bio wheel. I would have gone with a sump! Anything with a filter pad or is designed to trap waste will/can cause a nitrate problem.

 

[trippkid]

How much water do you change? Maybe try changing water every wk or 2. I think for what you have in the tank you could probably feed less or try every other day. Also, skimmer my need upgraded or modified somehow, had one before on a small tank and threw it out within a wk.

 

[inawe]

I've been changing about one third of the water at a time. I'll try changing every 1-2 weeks and see if it helps, along with feeding every other day. I just don't want anything to starve, and every time I do feed, they all act like they are starving to death...they come running, tripping over each other, falling off the rock (or jumping!)!

 

[trippkid]

They will act like that even if you feed them 3 times a day, don't worry they will be fine. I have a 120 w/ a trigger, parrot fish, clown, 3 chromis, yellow tang, hippo tang, hamlet, and they get fed 1 time a day a little bit more than what you feed, also many snails, crabs, cucumbers, corals, you name it. Also, only change about 10to15% if doing every wk and maybe 20 to 30% at the most every 2 wks. If you plan to keep the canister filter you will need to replace or clean the mechanical filtration very frequently.

 

[inawe]

I was initially working on a sump/refugium, which I put a lot of time into as far as ordering, waiting, building, etc. Then the day came to hook it all up. I got the overflow box set up, and the water flowing :cheer: ...turned on the return pump and my husband said "Oh, NO! It sounds like a tractor coming through the living room!" Then we heard the slurping sound of the overflow.

I would REALLY like to go back to the sump, so if someone can guide me to an almost SILENT pump, and tell me how to make the slurping stop...??? :help:

 

[pbienkiewi]

What kind of overflow box do you have ? GPH size of the drain ? Does it have a pump on top ? How deep of a sandbed do you have ? What are you planning on putting in the sump ? sand with live rock ?
I use to have a sump with the pump on top. I hated them WAY to noisey.
With my 55 and 30gal I never used a canister filter. I have rock and sand in my sumps.

 

[inawe]

I believe it is a CPR...the small one with only one U tube and it says a flow rate of 300 gph. The pump is a Rio HyperFlow 14HF. It is a submersible pump that goes in the sump. My sandbed is about 3 inches in my dt, and my intentions were to use sand and lr with plants (?) in the sump. I know from all the reading that the sump is far superior to other filter systems, but I if I can't find a way to cut out most of the noise, I'll have to stay with the canister for now.