Tank/Filter/Invert/Sand Question.

[krazykanuck]

Hey everyone!Info about me:
Im helping my father with his tank. Due to health issues he has not been able to maintain the tank, so that has been my job for the past 3 months.
Finding these forums, i have been reading them and figured i would post my questions all in one quick message for anyone who could possible answer them. Here i go!
Info on the tank:
Tank has been running for 4 years.
150 Gallon Saltwater, 4 powerheads working off a wave master, uv water filter, Fluval FX5 filter.
All levels on the tank are good. Clear water, healthy fish. 1/2 dead and alive coral.
Fish:
2 x Yellow Tang, 1 x emperior angel, 4 x blue tiny fish.
The Questions!!! Dun Dun Duuunnn..
1. Coral "sand"(looks like very small pieces of coral) on the bottom of the tank. there is no filter under it, however the sand is full of fish feces(poop). To clean it can i just take say 1/3 of it out and replace it with new? If i stir up the bottom the tank gets cloudy and stinks.
2. Crabs. They dont live. Im assuming the Tangs and the Angels are eating them. Even the BIG one. We also had a cleaner shrimp in there.
For about a year now they go missing. I cant see them dying as they guy in the store told us they normally survive everything. Other then getting eaten. Thoughts?
3. Fluval FX5. Seems to work great however lately it seems to get clogged. Air pockets in the filter stop it from filtering water. The top later my father thinks is getting clogged which is stopping the flow, but that doesnt account for the air in the filter.
I took it apart today, top was a bit dirty, but thats a given. No cracks on the filter and the lid looked to have a good tight seal. Im stumped..
4. Other fish.
With the list above, my father is also looking to get a larget Bat fish. What else would go well in the tank that has a lot of colour? Any thoughts are welcome. The 2 tangs are agressive. the angel isnt too agressive. seems to have taken a spot in the tank. =)
These are great forums! thanks in advance for any help that can be given. Im hoping to make my fathers tank look incredible!

<-- Spot!
iain
Edit: Some horrible spelling.

 

[salt210]

1. use a gravel vac to vacuum it out during a water change
2. its possible, but I doubt those fish are eating your C.U.C. probably due to water issues.
3. Canister filters are not a good idea when it comes to saltwater fish keeping as they tend to need a lot of maintence.
4. Batfish would be iffy as to the species and care needed for it. has he looked at tangs at all? he has choices but it will need to be able to take care of itself with that angel in there

 

[krazykanuck]

Thanks for the reply salt210!
The canister filter has needed little maitenance in the past few years. Just recently it has started acting up. I think he has only had one problem with the tank in 4 years.
All water tests are good. Well in the past 3 months. not sure about before. Ill ask him about the levels before when crabs were vanishing.
He had one bat fish in there for about 6 months. one of the fish most have attacked it(so i was told) and it died. He said he was looking to get a blue faced angel.
I would love to see a blue tang in there, but the shops around here never seem to get any in, and if they do, they seem to die at their store.
We have a gravel vac thats we use when doing a water change. but i dont think he used it that often before to stir up the gravel to remove the feces. Would that be the best way to continue doing it? or cleaning it out like i suggest before a good idea?
thanks again for your comments.. much appreciated

 

[meowzer]

You do not want to stir the sand....you will put too much "bad" into the water...you want to carefully vacuum it as Salt said.

 

[krazykanuck]

Meowzer,
I figured that wasnt too good floating around in the tank. I will be more careful during the next water change. I just wasn't sure if there was another method of cleaning it out because i dont think he really cleaned it out in the past. Atleast not very well.

 

[deejeff442]

i cant believe the water tests good if there is fish poop on the bottom.
that should never happen,4 powerheads seems good but obviously not eneough or dont flow eneough.
is there live rock in the tank or just the canister and powerheads?
get some snails to clean up the debrea.
you shouldnt have to clean the sand except for maybe an algea bloom.
list the fish you have,if you already have an angel you probably dont want to add another.
if a shrimp dies the crabs will eat it snails are more hardy than crabs,if you dont supply bigger empty shell for the crabs they will kill each other for a bigger one or just die off.

 

[salt210]

deejeff442 its not sand, its CC.
KrazyKanuck try and slowly moved it back and forth in one spot to get it to do down to the glass as your doing this make sure the tube for the vacuum is sucking this stuff up into it and not just making a mess.
the thing about these canister filters is that if they arent maintened very well they become nitrate factories, also they must be periodically pulled apart hose by hose and cleaned as you have found out.
the batfish is more of a peaceful(passive) fish if I am not mistaken

 

[locoyo386]

Hi there,
One point of advise since the tank has been running for 4 years. I do not know how deep your subtrate is nor if it had been vacumed on a regular basis. If it has not been cleaned on a regular basis and it is at least 2"-3" deep, be very carefull cleaning it as you might crash your tank if you are not, and/or clean the whole thing all at once.

 

[krazykanuck]

Batfish are very passive.. he lived a long time in the tank before. i think my father was lacking on the feeding of the fish and they attacked it.
The small blue fish are "Comerans" likely spelt wrong. VERY active little blue fish.
I totally cleaned the filter on the tank about 2 months ago.. stripped it down and washed out everything. Since i have started the tank is crystal clear.
Im doing a water change(about 1/4-1/3 of the water) every month. since then the fish seem more active and the levels are good.
Ill do it the way you are suggesting. Im also going to get a bigger bucket. this one fills too quick with the gravel vac im using.
Thanks again everyone. Much appreciated for the help!

 

[deejeff442]

oh sand my bad.
i used to have cc on my tanks of course that was over 10-15 yrs ago but i had no problem vacuuming it .it did trap alot of stuff in it.