Milky water

Hi, hope someone can shed some lite on my tank. I have a 20 Gal. hex sw tank, a 150 penguin biofilter, no live rock or coral, crushed coral on bottom, and temp is around 76-78 degrees and the tank is about four months old. Never had a problem with it, always crystal clear. I do a 50% water change once a month. About 10 days ago the water started to look cloudy and I had 2 fish die. The water got more of a milky color for the last 8 days. I did a water change and had my water tested all levels were fine including amm. Any suggestions?

 

when you set the tank up, did you rinse the sand? or did you use live sand? what kind of fish did you have and what do you have still? we need lots of info to help figure out whats wrong.

 

I didn't rinse the sand. It was live sand. I have a very small yellow tang, a general starfish, 2 black seahorses, a turbo snail and some hermit crabs. I lost a small blue tang and dwarft flame anglefish.

 

what about a protein skimmer?

 

Sounds like a possible bacteria bloom but we need way more info. what are your water tests coming out at? What type of media are you running in your penguin filter?

 

I'm using what the filter came with, the wheel and cartidge. The guy at the local FS said the levels were all fine including ammonia. Today my seahorses don't want to eat.

 

Also, what is a bacteria bloom and what does it mean?

 

You don't have enough surface area for the bacteria to inhabit (why people add live rock) for the Ammonia that your bioload is putting out. As a result, the bacteria that is normally on the LR is having to live in your water column making your water milky. The reason you're not showing Ammonia is because all of those bacteria are nabbing it before you can test for it.

 

Stop doing monthly 50% water changes- this is way too large of a water change to do all at once. Instead, do weekly 10% water changes, or biweekly 20% water changes. Secondly, while you have a bacterial bloom it's best to not do any water changes at all until it stabilizes. Run some activated carbon in the filter. Consider investing in some LR as extra biological filtration once this whole mess is over.
Get rid of the tang. A 20 gallon aquarium is no place for a tang, regardless of how small it is now. Also, seahorses are a very specific and fragile creature- they should really be kept in specimen specific aquariums, and not mixed with larger more agressive fish (like tangs- especially ones who don't have enough room to swim around and are likely to be a little bit more on the agressive side).

Regardless, you said you lost a small blue tang and a dwarf angel fish... SO you had these 2 fish, plus a yellow tang, plus 2 seahorses in a 20 gallon tank? You sure you couldn't fit that sand shark in there too? Fact is- aside from the seahorses, the rest of those fish require an aquarium of roughly 100 gallons. Please do some research on the fish you are interested in purchasing before you purchase them and stuff them into a cramped aquarium.

(By the way, sorry for being so harsh- just get tired of seeing the same EASILY AVOIDABLE errors happen so often. - If only people did 10 minutes worth of research before they jumped at things)

 

I have to agree with the others. Tangs and dwarf angels produce a fair amount of waste, this will build up in your system. Normally it's not big deal as the bacteria in the sand and the rock will dispose of it safely. As the others have said, you need to slow down. I would buy some rock, even small pieces and put them in there. I would also return/trade in the tang and sea horses. Then rethink your fish list.