different types of algea, and calcium questions:

Question

----I'm sorry to keep pestering you, but I don't know what you mean with the description of the filter.  The name of the filter is the Whisper 20 and it uses Bio-Bag filters.  They are like grey fluffy pads that you put this carbon thing in the middle.  I'm also sorry to say that my Lawnmower Blenny has died.  A couple of days ago he started acting funny, falling over on his side and acting like his left fin wasn't working, just flailing around.  I immediatley brought water sample to the pet store and they said everything was fine.  The next day I lost power for about 24 hrs, I was up the whole night heating water on the stove to keep the temperature up.  I set my alarm to do it every two hours.  When I awoke the last time I found my blenny dead being eatin by my hermit crab.  Any suggestions why he took a turn for the worst.--------------------------------------
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-----Question-----

-I use a carbon filter which I change once a month.  Do you think that is the appropriate time-span?  I also change 5 gallons of water at the same time.  I was looking into a protein skimmers and such, but I do want to upgrade my tank and don't want to replace all the equipment.  I was also looking at over the tank power heads or maybe a air stone system to help aerate the water.  Do you think my original filter is doing enough or should I invest in an additional source of bubbles.------------------------------------------
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-----Question-----
    I have a 20 gallon salt water aquarium.  I have about 11 pounds of live rock, 15 pounds of live sand, 2 clarkii clowns, 1 lawnmower blenny, 3 small hermit crabs, 2 turbo snails, and 1 emerald crab.  I've noticed the growth on the live rock some green and red patches, almost branch like 1/8 or so long easily broken off objects, and some cobweb or cotton looking substance between rocks.  I have also noticed a brittle worm or two woven in the rock.  Does any of this sound familiar.  I eventually would like two add a mandarin goby and maybe another small fish.  Far-off I would like to add anemone and corals once I can research and upgrade my lighting system.  Should I buy more snails/crabs.  I also bought a calcium supplement it's directions state to use a cap-full a day for a fifty gallon tank depending on coral/snail/crab load.  What should I use I've been using a 1/2 cap full every three days or so.

Thanks for your help
Lisa
-----Answer-----
hi, the "cobweb" looking substance is from filter feeding fauna, nothing to worry about at all. there is some mixed opinions about bristle worms, personally i think they are a good thing to have in your tank (not for your hands if you touch 1) they eat all leftovers on the rocks.

with regards to a mandarin goby, i wouldn't unless you have an abundance of copeopod life in your tank, its their staple diet. very few mandarins will take frozen food or flake, they hunt around all day for their meals.

to be honest, without knowing what type of filtration you use, skimmer, carbon, PO4 media ETC i would say your tank is at its limit with regards stock, maybe add a couple of cleaner shrimps but thats about it i'm afraid. same goes for the anemone, they need very good water conditions and a good light source. this is near impossible in a smaller tank....good excuse for an upgrade if you ask me...

for the calcium suplement get a good test kit for calcium. this will measure the levels in your tank. if you take 3 tests and average out the results you should get a good indication of your level. it should be above 400

and relax....hope that helps
-----Answer-----
the time span for the carbon replenishment seems fine. to be honest i would invest in a skimmer, it removes quite a bit of muck that would normaly stay in the tank.

If by a carbon filter you mean a reactor (only used for carbon) i would ditch it and get a half decent external filter, get some media bags and get some phosban de-nitrator and carbon in there.

an airstone does very little for gas transfer in an aquarium, i would get a powerhead and have it so its disturbing the surface of the water, you will oxegenate the water much better this way, and add much needed flow. you are aiming at 20X, minimum, the tank volume per hour when it comes to water flow.

hope that all makes sense?
good luck
paul.

Answer
i am sory to hear about your blenny!

i have never heard of that type of filter before, but if its doing the job ok..... well if your water perameters were ok, it could have been any number of things that killed your blenny, whats your SG and PH at? i have no idea if blennys are a hardy species but it sounds like a failure of an internal organ.

also heating sea water on your stove isn't a good idea, boiling sea water or overheating it changes the chemical properties of the water. more importantly it removes most of the oxygen from the water, which is never good.

i hope everything turns out ok, and you don't need to worry about pestering me, thats what i signed up for.