High Tide Aquatics

Sometime I hate owning clams and coral.....

[quote author=GreshamH link=topic=3137.msg34615#msg34615 date=1203637306]Kalk still won't give a "spike" what hobbyists know Alk as being. Of course PH relates, but not in terms of this discussion as you can boost your PH to 12 with KALK and it wouldn't reflect in your current total ALK when measured using normal hobbyist methods before or after the dose.[/quote]

Ok, for the sake of demonstration, I went ahead and simulated a couple of fast kalk additions and measured alk to get some sample readings.

The premise is that someone quickly doses ~4 liters of saturated kalk water to a tank with 75 gallons total system volume.

(4 liters X 1000ml/liter)/(75 gallons)/(16 cups/gallon)=3.3 ml/cup

So to make things easy, I figured 4ml of kalk water to 1 cup of tank water would be a reasonable approximation.

I took an 8oz sample of tank water and tested the starting alk using the API reagent with my high precision syringe method.

Next I dosed 1ml of saturated kalk water to the 8oz sample to simulate adding 1/4 of a days worth of top off very quickly. I stirred the sample then measured again using the modified API method.

After that, I added 3ml of saturated kalk to the sample, mixed well, and did a third alk test.

Results as follows:

tank water + 0 ml total kalk addition : 3.21 meq/L
tank water + 1 ml total kalk addition : 3.39 meq/L
tank water + 4 ml total kalk addition : 3.85 meq/L

So that pretty much shows that fast kalk additions cause jumps in alk levels.

What can make things worse is if you "dose lime water twice a week ( 5 gallons drip in)", and you don't dose slowly and continuously over the week to match alk consumption and keep your alk stable...

i.e. you dose quickly so that there are some days during the week where you don't drip kalk...

Your clams and corals will suck your alk down low on the non drip days. Then you bump it back up with the next batch that you drip. And that's on top of the pH swings from the nondosing/fastdosing procedure.

Using the above numbers as an example....

Let's say that your system uses 3.85-3.21 meq/L per day = .64 meq/L per day

If you did daily single batch fast drip, your alk would swing from around 3.21-3.85 meq/L.

If you dose your alk 2x per week at a fast drip(say over half a day period), you would have 3 days of alk consumption before you dose again.

Very roughly speaking, you would have an alk swing on the order of 3 x .64 meq/L = 1.92 meq/L

So if your alk at the top end was 3.85 meq/L, your low would be towards 1.93 meq/L.

Then you do your next fast drip and your alk would shoot from below 2, all the way back up to ~3.85 meq/L.

If anything like that is happening, I'd expect problems with clams, montis, and acros.
 
I always use a slow drip...about 1 gallon an hour. I only do top off twice a week. I don't think its the spike issue, otherwise the other clams in my tank would show stress and my SPS as you say. Its still alive and the crab is too in a container. its dying very similairly to that huge 17 incher clams I lost last year...only difference is that it didn't spawn like that one. it is my biggest clam, but my 2 gigas close behind it shows no changes so far. My last alk test was 2 days after my last drip, and it was 8. I will test again today and tommorrow since I am dripping in again tonight just to follow up. Anybody want a free crab? I read that clams have comensal shrimp( I used to have one), but couldn't find anything about crabs in clams....those pinchers it had must hurt!
 
[quote author=Apon link=topic=3137.msg34731#msg34731 date=1203718825]
I always use a slow drip...about 1 gallon an hour. I only do top off twice a week.[/quote]

1 gallon per hour is not a slow drip.

Also you said that your dKH starts at 11, and drops to 8 after 1 day of not dosing. Your alkalinity consumption is 3dKH/day.

If you dose 5 gallons every 3.5 days at a rate of 1gph, that means that you spike your alk then it drops over the next 3.29 days. (3days+(12-5)hrs/24hrs/day)

3.29 days X 3 dKH/day = 9.87 dKH

You're basically using up all your available alk in between doses then bringing it all back up in 5 hours.

Here's a good article on kalk dosing:

http://reefkeeping.com/issues/2005-01/rhf/index.php

Some useful sections:

"The calcium ions in the solution obviously supply calcium to the aquarium, and the hydroxide ions supply alkalinity. Hydroxide itself provides alkalinity (both by definition and as measured with an alkalinity test), but corals consume alkalinity as bicarbonate, not hydroxide. Fortunately, when limewater is used in a reef aquarium, it quickly combines with atmospheric and dissolved carbon dioxide and bicarbonate to form bicarbonate and carbonate:

4. OH- + CO2 à HCO3-

5. OH- + HCO3- à CO3-- + H2O "

"Saturated limewater has a conductivity of about 10.3 mS/cm at 25ºC, and contains about 808 ppm of calcium and 40.8 meq/l of alkalinity."

"4. Delivering a small amount of limewater all at once. Adding 1.25% of the aquarium’s volume (1.25 gallons of limewater per 100 gallons of aquarium water) as saturated limewater all at once raises the pH by 0.6 to 0.7 pH units. Such an increase is clearly too large. Adding a smaller portion all at once can, however, be acceptable. Adding, for example, 0.25% of the aquarium volume (0.25 gallons or 1 L of limewater per 100 gallons of aquarium water) will raise the pH by only 0.1 to 0.2 pH units. Unless the pH is high (>8.4) before the addition, that amount is likely acceptable."
 
ok, but wouldn't you still think my other animals will show signs of stress if it was the Alk/ph spike? FYI - I have been doing this dosing this way for like over 2 years, all of my clams are older than 1 year with me. A bunch my my lps and softies are 3-4 years old, only a few SPS that are 2 years old.

That time I tested it was 11. It would be interesting to see what my alk is now 2 days after my last test( which was at 8), before I drip again, but I will try to slow the drip more. Since I don't really test that often its hard to say, but I agree that stable is better. Thanks for the feedback.

Next I guess you will tell me to use a skimmer again : )

I still like to believe it was the crab! : )
 
You know it being all of this close to the lunar eclipse I'm beginning to wonder if the clam perhaps was trying to spawn and simply stressed. Just throwing out another maybe...
 
Does spawning stress the clam?

Environmental stresses will trigger spawning though. It's nature's last ditch effort to continue the species.

A lot of times if you see a clam spawning in the tank, it's a sign of something already gone wrong, no?
 
that's right, stress can cause a spawning too. My big monster clam spawned last time ( 2 days worth), I wasn't too worried because the previous owner says it did that once a year, that triggered some others to spawn as well. Only the big one died that time. I still have all the other ones. This particualr one wasn't part of that group, but hasn't spawned at all in a year.
 
[quote author=Apon link=topic=3137.msg34742#msg34742 date=1203723554]
ok, but wouldn't you still think my other animals will show signs of stress if it was the Alk/ph spike? FYI - I have been doing this dosing this way for like over 2 years, all of my clams are older than 1 year with me. A bunch my my lps and softies are 3-4 years old, only a few SPS that are 2 years old.[/quote]

Well, I've been saying for the last 2 years that you might have alk issues... after you told me that for some reason it's hard to keep montis in your tank.

Depending on the extent of parameter fluctuations, different animals will show differing reactions. Just because the stress isn't visible to us doesn't mean that there isn't a problem.

You know how toxins have an LD50? Lethal Dose 50, where 50% of the test subjects die. Just because half are killed, doesn't mean that the other half are doing well.

Another thing... you're using Elos alk test? You could be off by as much as 1dKH, so your alk consumption may be only 2dKH/day instead of 3.

So, best case scenario:

2 dKH/day X 3.29 days = 6.58 dKH drop before the next batch drip.

So if you're starting at 11, you end up at 4.42 dKH

Natural seawater is ~7dKH.

With your setup, best case is that you drop from 11 dKH to NSW levels after 2 days.

11dKH - (2dKH/day x 2 days) = 7 dKH

So for 1.29 days, your clams and whatever are trying to deal with lower than NSW levels before you respike.

You may be stressing the system, but only to the point where some of the animals show obvious signs.
 
Hehe...

Use my modified API high precision alk test method :D

Use my 3.6meq/L alk test standard too. Only fie dollah a bottle for BAR member, haha :D
 
Yes its a elos kit. It was that only those red digis.... multiple frags! I can't keep, the greens and others ones were ok....always that one digi. ( I have another from Tong that has been doing well - since Tom suggested I check the salinity)

Good stufff to know Norm, thanks.

I still don't believe its an alk issue, but I will see what my alk is tonight.....I do have a Calcium reactor and I do weekly water changes too. I haven't loss many sps in a year (1 red millie), I think like 3 frags of red digi....Only 1 fish ( except for the 3 that jumped out because of my 6 line) I like to believe my tank is pretty stable due to the age of it, but who knows....xenia ok, other sps growing and extended, cloves ok, zoos ok. most of you have seen the tank several times over the last 2 years. Time for a tank tour again?

Maybe I am complaining too much...I just don't like it when things die. Its the crab and I am sticking with it. : )
 
I hope this is an appropriate side question. I have a crappy redsea alk test (match the color) and a several year old Ca Salifert kit which I think is giving me incorrect readings (age?).

What are the recommended alk/Ca test kits these days? Reasonable accuracy is important to me, so that probably means titration type tests.
 
I have the elos ones that i like, but can't give you a good answer on that question....I think age will affect the kit.

As you can see I only have questions - Norm, has answers. : )
 
Arnold, just because only one of your clam got affected doesn't mean others are not, they probably are but to a lesser degree because they are healthy and are more hardy, this particular clam is probably already is weaken by something else and this has cause it to stress some more. One example is alk swing causes burned tips in sps corals, but some corals are not affected depending on the species and how hardy they are.
 
Only reason why possible spawn is because I was changing water out the display at work and yes the water change triggered massive spawn of something in the tank water. Came in today and skimmer cup was full.
 
With clams, temp spike can trigger spawning.

Also one clam spawning will induce the others. Kind of a reef orgy thing. Maximizes the chances for babies.
 
Hehe...

Also was reading earlier today about clam culturing facilities where they get the clams all ready to spawn and then they throw in some macerated clam gonads to make them do their stuff.

Ouch!

:D
 
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