HOW TO STOP A TANK CRASH in progress: an FYI

Sk8r

Staff member
RC Mod
tank crash: when your chemistry goes south, your fish and corals die, and your tank ends up a toxic soup.

Warning signs: ANY of these warrant a fast series of tests and remedial action: tucked in corals, fish up at the top gasping, or all hiding, green water, mucky brown water, test results off the edge, high temperature, as in, 84 and upward.

Actions to take and why: 1. relieve the bioload. Fill your qt with new saltwater. Use a mixing pump to accelerate the mix, or buy saltwater from your lfs. Move your fish and inverts there asap. This MAY slow the crash down. Meanwhile look over your corals and put the heathy ones in with the fish. Use standard qt procedures for an uncycled qt: ie, test 2x daily and change the filter floss daily. HIGH oxygenation.

Now create a second qt and start getting the iffy corals into clean water.

What you've just done: 1. you got the fast-respiring fish out of there. This relieves demand on the oxygen; you saved your most viable creatures; you made sure that none of these are going to die and start rotting, which can accelerate the crash bigtime.

2. you got the iffier corals, the ones with damage, separated from the ones that are definitely going to live. If you have any anemones or something really iffy, put it in yet a THIRD container, always with aeration and filtration. If it's late by now, and you're falling on your face, you CAN go to bed on this situation, or just continue on to a water change if you've got the fortitude and the water.

3. Do a 30% water change [do you get the picture that you always need far more salt on hand than you expect to need, and that buckets and a strong mixing pump are a good idea?] and give it a while. Do it with colder water if you're having a heat issue. Go tend your fish and corals and just let it alone for the night to see how the 30% worked. [This is in total going to be a 50% water change, and best do it in stages.]

4. Next day: Do another 20% water change. This amounts to a 50% water change. Hopefully you've now straightened out your chemistry, partly by putting in 50% well-balanced water; you've oxygenated the tank, and you've saved your specimens. If you now test ok, start putting in your inverts first. Day by day, as they succeed, add another SMALL group of inhabitants until everybody's happy. Starting with inverts is because a) they're tough and b) they can 'test' the ability of the sandbed to handle their poo without another incident.

Crisis hopefully averted. By preventing death in your tank, you saved the water from worse pollution, and you gained respite for the tank bacteria to catch up with the situation; secondly, you kept your livestock healthy; thirdly, you altered the water balance with the 50% water change, which is not large enough to cause another cycle, and which will dilute whatever unhappy chemistry is going on in there. Not only test but write the results down: under stress you may confuse a number and go a wrong direction. A written record for a hobbyist under stress is a Good Idea.

This is also the sort of thing you can direct a tanksitter to do if you get the dreaded Something's Going On With the Tank call while you're suntanning in San Diego. None of these actions are really beyond the capability even of a novice tank sitter except the tests, if you've got the materials in your supply closet.
 
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I'll put this in my blog: if you have spare time and want to read, just click the blue number under my avatar and you can find these things.
 
Lol. Just a couple of notes about equipment disposition during a crisis. Leave your lights on the tank: your corals in qt can get by for a week with no light. What you do need is to draw a fill line on the qt to mark evaporation, and if you can move your ato over to the healthiest qt you will make things a lot safer.
 
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