Are cuc's real?

[fish farmer]

It depends on how you run/set up your tank. If your skimming, flow, feeding, etc, etc and adequate where you don't need a CUC, more power to you. If you have limitations with your ability to be the CUC, then they can be of service. Just don't fall into the trap of overstocking your CUC an expect they are the only ones to take care of all the cleaning.

I've been doing algae eradication on my tank for about a year. One pesky red algae eluded eradication. I read that Mexican turbos eat red algaes. I put four in my 29 gallon tank. It has taken about a month but the are doing a great job and taking care of it.

 

[reaper0268]

If you don't have a balanced clean up crew your tank will likely fail.

Don't buy the ridiculous packs. 3/4 will die once the mowing rampage is over.

Micro fauna, bristle worms, small brittle starfish, a big brittle star, cerith snails, narssarius snail, trochus snails, nerite snails, stomatella snails, an army of elephant slugs, scarlet reef hemits, an occasional female emerald crab, and myself all make up my balanced clean up crew.

 

[TexanReefer]

it's both an extra thing for an lfs to sell and it helps keep a tank clean, if they are healthy animals
as crabs grow, but even moreso snails, they take up nutrients from the tank to increase their body mass, and they also remove nuisance algae. So, while they need food to survive, they help transfer nutrients from algae into their bodies. That said, I don't think crabs are as good at "soaking up" nutrients as snails because crabs dont grow as large and their actual muscles are small compared to their exoskeleton. I wish I could have snails in my tank but I have a puffer.

The majority of nutrients consumed by almost any animal is expended via energy. So essentially snails and crabs consume excess nutrients and use them for metabolic function, building body mass, and expending energy moving around the tank. Then a small percentage of the nutrients they consume are expelled as waste.

 

[PatW]

OK. Basic ecology here. Biological entities structure ecosystems.

First, there are producers. These are nearly always photosynthesizers. Think plants. They convert energy in light into chemical energy.

Second, there are primary consumers. These are herbivores like cattle or grasshoppers.

Third, there are secondary consumers like insect eating birds or wolves.

And then you have decomposes. These process dead material like dead plant leaves, corpses, and feces. By doing so, they release the nutrients bound up in unprocessed organic matter making it available to plants. They complete the system.

The above scheme is simplified.

In our reef tank, the CUC consists of primary consumers that gobble up nuisance algae a primary producer. Our snails serve this purpose and I bet they consume any dead algae also making them decomposers. Turbo snails are an example.

Also uneaten food or dead fish can be consumed by bristle worms. They serve as decomposers and secondary consumers.

If you want a good looking tank, you need a good and diverse clean up crew. I doubt that they add much load to the tank and even the little they add is more than worth the price.