Some issues that boggle my mind???

[amp123dime]

My damn crabs are clipping the prickley things off of my black sea urchin?? I figured buying the sea urchin would help with eating the algae off the glass but he hung out at the bottom and got beat up by my crabs?? now he isnt moving around although he is still alive should I kill him and throw him away or let him live and see if he can survive the crab torture??( my 2 year old daughter was crying saying"my lub him") has anyone had a sea urchin with crabs before?? I have had a lot of algae since I put my 192 watt lunar aqualight in my 46 gallon bow which was to be expected but what will eat the algae off the glass the crabs wont should i get like 10 snails??? Also I have 2 30-60 gallon whisper power filters on my 46g bow. Someone told me they were nitrate factories what filter unit can I buy that will do the job for my whole tank like 500 gph or more???? I think H.O.T is the best way to go am I wrong????

 

[MT79]

First off, crabs are evil heh. They are opportunistic predators which means they will eat anything that they can catch. Whether it is snails, urchins, coral, or even fish as they get larger. I recommend removing the crabs and getting a clean up crew for algae and detritus. A few different types of snails, an urchin, serpent starfish, and/or ornamental shrimp such as cleaners are all good members of a clean up crew.

I have had a lot of algae since I put my 192 watt lunar aqualight in my 46 gallon bow which was to be expected

What type of source water do you use(ex tap water, RO or RO/DI)? With higher light levels smaller amounts of algae fuel are going to become an issue. Nitrate, phosphate are the two biggest causes of nuisance algae outbreaks. I would test for both in your source water and tank. NO3 should be <15 ppm and PO4 =/< .03 mg/l ideally to avoid issues.

Also I have 2 30-60 gallon whisper power filters on my 46g bow. Someone told me they were nitrate factories what filter unit can I buy that will do the job for my whole tank like 500 gph or more????

I'd recommend the "berlin method". All you need is 1.25-2 lbs LR per gal, good water flow (15 x per hour tank turnover minimum) and a GOOD skimmer. Other than those things, a place to run GAC or a phosphate reducer like Rowaphos or Phosban is good to have. I would use a HOB filter w/ no mechanical filtration, only chemical media. Mechanical filters ie. sponges, floss, tend to clog and need cleaning once or twice a week. If not cleaned regularly they start producing excess nitrates.

 

[Kurt_Nelson]

I've also got about 200W of light on a 46g bow. Probably the same Coralife fixture as you! I wouldn't say you should expect more algae - I really don't have any issues. (There, I probably just hexed myself.)

I'll just second what MT79 said - check your source water and keep your nitrates low and your phosphates undetectable. Rinse out any sponges (in old saltwater) in any filters on a weekly basis - that'll help keep them from becoming little nitrate factories. I run a Marineland HOT (250gph) canister on my bow - just to house some Purigen. But I still rinse out the sponge/cannister weekly with my water changes.

In addition, I'd get 10-12 snails to start with. Personally, I like the trochus best followed by astreas. Astreas tend to be clumsy and expect to loose a few due to them tipping over and the evil crabs coming in for the kill. Regardless, they're both good algae eaters to help keep things tidy. They won't keep your glass spotless, so if you haven't invested in a cleaner magnet now would probably be a good time.