der_wille_zur_macht
Team RC
I've never really paid attention to cleanup crews or who eats what, because I mainly believe in eliminating problems at the source instead of cleaning up afterwards - to date, most of my tanks have been stocked with a very low level of somewhat random assortment of snails and sometimes a few smaller hermits. I've never really had nuisance algae blooms so this subject hasn't really been on my mind much.
Well, the bi-level 60g tank I'm borrowing from Flanders has given me an unintentional opportunity to experiment. For those who don't remember, there's a glass panel glued horizontally about halfway up the tank on one end, such that there's an isolated, raised sandbed on that side. Here's a photo from when it was first set up last month:
This panel creates a bottom-level lit portion (left end), a bottom-level cryptic portion (right end) and a raised lit portion (right top).
I seeded it with sand, rock, and cleanup crew from the 360g. It had dwarf cerith, nassarius, florida cerith, and an assortment of smaller hermit crabs (plus one or two gigantic hermits that reefcleaners.org threw in with the order). Probably a dozen or two of each snail and 20 - 30 hermits total. Much more than I would normally put in a tank this size but I had them on hand from taking the big tank offline.
Anyways, here we are a month or so later, and it's been running fine. The only real "issue" was a light coating of diatoms on some of the rock. A few days after they appeared I realized they were only appearing on the rock and sand up on the top ledge. This troubled me, because - clearly - conditions up there were identical to conditions on the bottom of the tank, in terms of flow, nutrient levels, water quality, lighting, and so on. After all, we're talking about two spots in the same bloody tank. So, the big question was, what was causing the isolated diatom bloom? Why were they only appearing up on the shelf? There wasn't a single solitary spec of diatom growth elsewhere in the tank.
I then realized something. When I tossed the cleanup crew in, nearly all of them "landed" on the bottom. The snails could climb up to the upper shelf and were evident there, but the hermits had no way of getting up there. Since the snails had access to the upper level, it was clear that they were not really cleaning up the diatoms at all. So, I concluded that it must be one or more of the hermit species keeping the bottom clean.
So, last week, I grabbed a few of each type of hermit and placed them on the upper level. There were blue legged hermits and a slightly larger striped variety I've seen sold under a variety of names, plus one of the gigantic hermits. Sure enough, every single time since then that I have looked at the tank, I've seen hermits crawling on the rock, eating away. I could see obvious patches where they had "mowed" the diatoms. It was almost exclusively the striped hermits doing the work - the blue legged hermits seemed to stay hidden and the giant hermit only seemed interested in knocking frags over.
As of this morning, there isn't a single spec of diatom growth anywhere in the system. It's literally sparkling clean. The sand is bleach white from edge to edge and the rock is spotless. The area up on the shelf is just as clean as the rest of the tank.
I'm still a firm believer that to really solve these sorts of algae/diatom problems you have to attack the source (flow, nutrients, etc) but sometimes you need a hand getting at the nutrients already bound in the pest. And since this "experiment" occurred in a closed system I feel very certain that I can attribute the results to these specific hermits. Clearly this isn't groundbreaking news but I thought it was pretty cool that this shelf-system gave me an opportunity to observe cleanup crew members at work in two discrete portions of the same system so I figured I'd share the results.
For reference this is a photo of the hermit in question:
reefcleaners sells them as "thin striped hermits" but I've seen them sold under other names.
Well, the bi-level 60g tank I'm borrowing from Flanders has given me an unintentional opportunity to experiment. For those who don't remember, there's a glass panel glued horizontally about halfway up the tank on one end, such that there's an isolated, raised sandbed on that side. Here's a photo from when it was first set up last month:
This panel creates a bottom-level lit portion (left end), a bottom-level cryptic portion (right end) and a raised lit portion (right top).
I seeded it with sand, rock, and cleanup crew from the 360g. It had dwarf cerith, nassarius, florida cerith, and an assortment of smaller hermit crabs (plus one or two gigantic hermits that reefcleaners.org threw in with the order). Probably a dozen or two of each snail and 20 - 30 hermits total. Much more than I would normally put in a tank this size but I had them on hand from taking the big tank offline.
Anyways, here we are a month or so later, and it's been running fine. The only real "issue" was a light coating of diatoms on some of the rock. A few days after they appeared I realized they were only appearing on the rock and sand up on the top ledge. This troubled me, because - clearly - conditions up there were identical to conditions on the bottom of the tank, in terms of flow, nutrient levels, water quality, lighting, and so on. After all, we're talking about two spots in the same bloody tank. So, the big question was, what was causing the isolated diatom bloom? Why were they only appearing up on the shelf? There wasn't a single solitary spec of diatom growth elsewhere in the tank.
I then realized something. When I tossed the cleanup crew in, nearly all of them "landed" on the bottom. The snails could climb up to the upper shelf and were evident there, but the hermits had no way of getting up there. Since the snails had access to the upper level, it was clear that they were not really cleaning up the diatoms at all. So, I concluded that it must be one or more of the hermit species keeping the bottom clean.
So, last week, I grabbed a few of each type of hermit and placed them on the upper level. There were blue legged hermits and a slightly larger striped variety I've seen sold under a variety of names, plus one of the gigantic hermits. Sure enough, every single time since then that I have looked at the tank, I've seen hermits crawling on the rock, eating away. I could see obvious patches where they had "mowed" the diatoms. It was almost exclusively the striped hermits doing the work - the blue legged hermits seemed to stay hidden and the giant hermit only seemed interested in knocking frags over.
As of this morning, there isn't a single spec of diatom growth anywhere in the system. It's literally sparkling clean. The sand is bleach white from edge to edge and the rock is spotless. The area up on the shelf is just as clean as the rest of the tank.
I'm still a firm believer that to really solve these sorts of algae/diatom problems you have to attack the source (flow, nutrients, etc) but sometimes you need a hand getting at the nutrients already bound in the pest. And since this "experiment" occurred in a closed system I feel very certain that I can attribute the results to these specific hermits. Clearly this isn't groundbreaking news but I thought it was pretty cool that this shelf-system gave me an opportunity to observe cleanup crew members at work in two discrete portions of the same system so I figured I'd share the results.
For reference this is a photo of the hermit in question:
reefcleaners sells them as "thin striped hermits" but I've seen them sold under other names.
I'm definitely not claiming to be making any huge revelation here about these hermits being super awesome at tank cleaning, just thought it was cool that I could segregate them from different parts of a single closed system and hence witness their specific "tastes" for cleaning.
They created a little bit of glare in the room without something there to block them from view, but I didn't want to build a canopy, so I stuck that plywood there as a temporary measure. You're welcome to come over and see the tank in action any time.
