Nitrate ?'s for Randy

[3Watt]

Randy, at what level in ppm would nitrates have to reach before snails and other invertebrates (besides corals) begin to die?

I've read your article http://www.google.com/url?sa=t&rct=...iP5uf1-Z32wJIGOUQ&sig2=gjIA1KQf5Q0jBrSYkA46EQ more than once in the years I've been doing this saltwater thing but I right now I need some educated input on the effects of excess NO3 in aquaria.

All of the scholarly articles I've found either discuss nitrates effects over corals or other sessile invertebrates in the open ocean.


Any other input is welcomed by anyone.

 

[3Watt]

Habib? Anyone?

The facts are that I am in an argument over elevated levels. One side of the debate states that 160ppm would not effect fish,corals or mobile inverts.

I personally have witnessed mass bail out of snails and even a green brittle star when water quality was neglected. Those snails and hermits that couldn't or didn't climb out died. The only parameter tested was NO3 and it was well under 160ppm @ just over 50ppm.

I was hoping to get some expert input.

 

[Randy Holmes-Farley]

I do not really know how high they need to get before snails suffer.

Anyone know?

 

[gmate]

I've run my tank with 100PPM nitrates for several weeks with continued coral growth before. I've done water changes since then, but s**t happens sometimes and I couldn't be with the tank. No loss of inverts or coral. My leather toadstool wilted a little bit, but that's it. Everything else was still thriving.

 

[Habib]

Habib? Anyone?

The facts are that I am in an argument over elevated levels. One side of the debate states that 160ppm would not effect fish,corals or mobile inverts.

I personally have witnessed mass bail out of snails and even a green brittle star when water quality was neglected. Those snails and hermits that couldn't or didn't climb out died. The only parameter tested was NO3 and it was well under 160ppm @ just over 50ppm.

I was hoping to get some expert input.

I could not find a useful article. There is some about freshwater gastropods with the mentioning that in seawater the nitrate toxicity effect is reduced.

That, and my personal experience and knowing that there are plenty of tanks with elevated nitrate concentration (>50 ppm) without mention of issues like snails and hermits trying to escape, makes me believe that the observation you describe might have a different cause.

Nitrate concentration of say above 50 ppm might reduce the lifespan somewhat but I don't think it will induce a escape response.

 

[Habib]

OK, I typed "escape response" in my above post.... that made me decide to go search for that. Interesting stuff Perhaps not applicable to 3Watt, but still interesting.
Well at least it shows that there can be various factors involved.


"...(4) Escape responses
From the earlier work of Bullock (1953) it is evident that many intertidal gastropods use chemoreception to escape from starfish. Both this work and a later study by Feder ( I 963) reported that Tegula,Littorina, Acmaea and Haliotis all showed species-specific active escape responses when contacted by, or when in close proximity to, the predatory starfish Piaster. Several lines of evidence indicated that the response is chemically mediated. First, equivalent mechanical stimulation in the absence of a starfish generally resulted in animals like limpets and abalones clamping their shells tightly against the substrate. T h e response to starfish was generally an active lifting and rocking of the shell followed by locomotion away from the predator. Second, little or no response was elicited by contact with the tube feet of urchins or herbivorous starfish. This suggests recognition of species identity of the predator. Given the limited visual capabilities of many of these gastropods, chemical cues appear to be a likely explanation. Third, water that recently contained a starfish is often adequate as a stimulus. Recently, the active compounds in sea stars that elicit the escape responses have been characterized (see
300
R. P. CROLL
Section 111on stimulatory chemicals). Also Clark (1958)and Peters (1964)showed that gastropods can use chemoreception to avoid or escape other predatory gastropods....."


Above is from:

http://physiolws.bp.dal.ca/people/faculty/pubs/11_329.pdf



A LOT more if searched for "escape response gastropods".

 

[3Watt]

OK, I typed "escape response" in my above post.... that made me decide to go search for that. Interesting stuff Perhaps not applicable to 3Watt, but still interesting.
Well at least it shows that there can be various factors involved.


"...(4) Escape responses
From the earlier work of Bullock (1953) it is evident that many intertidal gastropods use chemoreception to escape from starfish. Both this work and a later study by Feder ( I 963) reported that Tegula,Littorina, Acmaea and Haliotis all showed species-specific active escape responses when contacted by, or when in close proximity to, the predatory starfish Piaster. Several lines of evidence indicated that the response is chemically mediated. First, equivalent mechanical stimulation in the absence of a starfish generally resulted in animals like limpets and abalones clamping their shells tightly against the substrate. T h e response to starfish was generally an active lifting and rocking of the shell followed by locomotion away from the predator. Second, little or no response was elicited by contact with the tube feet of urchins or herbivorous starfish. This suggests recognition of species identity of the predator. Given the limited visual capabilities of many of these gastropods, chemical cues appear to be a likely explanation. Third, water that recently contained a starfish is often adequate as a stimulus. Recently, the active compounds in sea stars that elicit the escape responses have been characterized (see
300
R. P. CROLL
Section 111on stimulatory chemicals). Also Clark (1958)and Peters (1964)showed that gastropods can use chemoreception to avoid or escape other predatory gastropods....."


Above is from:

http://physiolws.bp.dal.ca/people/faculty/pubs/11_329.pdf



A LOT more if searched for "escape response gastropods".

Thank you Habib, I wouldn't have thought to search "escape response".

The situation I witnessed occurred in my home. Two years ago the wife demanded that all of my tanks come down. Being seriously bummed as I sold off my corals and other livestock I shut all the equipment down except flow. One tank sat in our dining room, it had been neglected in this manner for over a month, I'm sure there were a few dead snails feeding the bio filter but the point is that one evening I noticed dozens of snails, nerites mostly on the floor around the tank. Looking further I found my large green brittle star had also climbed out and was behind a cabinet next to the tank. It was only out of curiosity that I tested nitrates. That is all I did test unfortunately.

Thanks again for the link and your time.

FWIW I sold my Hannah checker and went back to your Ca. test kits. That checker was just to touchy for me.