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55 gallon tank


Blue Ring
Jan 7, 2003
okmy 55 gallon tank was a seahorse tank but now my 30 gallon extra high is. i had a hair algea outbreak and i have it lights off and covered to kill it all. i was told do a week. does anyone know. also i decided to go with fishsupply.com I was wondering should i go with the medium bimac as the small might get lost and not find food?????
Hair algae hasn't been a problem for me long-run. What sort of prefiltration do you have for your water? You might have too much of a nutrient entering the tank. Or possibly a problem with your brand of salt. I can't make any specific recommendations there. I suspect my current algae issues are due to nutrients in a salt I switched over to, but it's REALLY hard to find reliable and user-friendly data on salts. Basically, you try a few, and settle on whatever you think works best for you.

For bimac size, I would actually recommend the small. The age of an octo is proportional to its size, so smaller ones are generally younger. Given the short lifespan of octos, this can be an important difference. I'm not completely sure what to tell you about food....someone else here would probably know what size of bimacs we could expect from Fishsupply and what sort of food is appropriate for that size. I suspect simply very small hermit crabs, ghost shrimp, and small pieces of fresh seafood would be just fine. If size was really an issue, you could order amphipods from someone like Florida Aqua Farms.

i can get really small hermits so im sure they would work. i think it was red sea salt that caused it. i used instant ocean then red sea now instant ocean. and it formed during the red sea salt.
Well, as I mentioned, the "science" of sea salt is so untrustworthy that I really can't swear any one salt is better...so it's prolly really irresponsible of me to make such a suggestion, but...I wonder if Red Sea salt is my problem. My detective story:

I've had a similar algae problem for some time. It's not what I think of as "hair algae"--coarse, filamentous green stuff--but rather more a slime algae and diatom sort of problem. Only hairlike/fibrous structure visible is on a very small, closely-viewed scale. Typically dark brown, with some patches of red (the red stuff is especially slimy, I suspect it's cyanobacteria.

This began right after my tank crash. At first, I thought I'd simply destablilized the balance of algae in the tank with the crash, but now I'm not so sure. I did massive water changes after the crash, of course, so I started to think that perhaps my prefiltration system was letting enough critical nutrients through that, with massive water changes, I concentrated too much nutrients in the tank. Theoretically this would mean the algae bloom would go away with time as the algae gobble up nutrients and I siphon away the alge. But it's persisted.

Right before the tank crash, I'd purchased a bucket of Red Sea salt on a great sale at Petco. I'd been using Instant Ocean previously with no problems. I'd started using it gradually, mixing portions of IO and Red Sea, mostly just IO. After the crash, I was low enough on IO that I used much more Red Sea. Quite possibly, then, my new algae problems are in fact the result of switching over to mostly Red Sea salt.

The algae don't seem to be HURTING anything, so I'll live with the problem for now, but I'll be trying some new salt when it comes time to buy again. Would anyone have suggestions on salt? Colin, I know, is very happy with Tropic Marin...I was surprised to find that I can order it affordably online, even after the steep shipping weight charges. I did some searching and found much discussion on salt on Reef Central. Quite a confusing mix of information there, but I walked away with an impression that Crystal Sea Marinemix Bioassay might be worth trying. Any other ideas? I don't mind trying something new, though I seem to know of at least one mix (Instant Ocean) that seems problem free for me.


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