sex of fish

Question
QUESTION: how can you tell the sex of an algae eater and an iridescent shark

ANSWER: Hi Melissa;

Iridescent shark males have darker stripes and are thinner than females. They would have to be mature though and those fish grow to be over 3 feet long. Not really suitable for aquariums, even though they are commonly sold. They are nervous guys, especially strong as they get bigger and can bust the glass and lights. They are farmed and fished in Thailand for food. How big a tank do you need? Think 1000 gallons or larger...Yikes! Here's a link to a photo of one that's not even full grown;

http://tinyurl.com/ytjcp5

Here's a profile page too;

http://www.aquariumlife.net/profiles/asian-catfish/iridescent-shark/100117.asp

There are MANY types of algae eaters and some are difficult or impossible to sex. Let me know which one you have or get a photo for me and attach if to your followup and we can go from there.

At Your Service;
Chris Robbins

---------- FOLLOW-UP ----------

QUESTION: i have a common plecostimus aldea eater or however you spell that

Answer
Hi Melissa;

I'm sorry it took me so long to get back to you. I've been sick.

Plecostomus can be sexed by comparing several of them in a group but they must all be the same age. Males have larger barbels usually but it's still not a sure thing. The barbels are basically their "whiskers" and can vary according to each fish anyway. There really isn't any other way to know unless they pair off and breed, but it's rare in the aquarium.

Good luck!

At Your Service;
Chris Robbins