Backyard Aquaponics
A place to discuss aquaponics

Well the trout went off the feed again two days ago...
Ammonia was at about 0.25... Nitrite 0. Noticed that the nitrates have come down from 40+ to 10+... but it could be related to all the broccolli coming to harvest size...

pH <6 I think. Have added some garden lime again.

The water has quite a bit of poop. Pump is running good, but as previously indicated, I don't think the strainer is allowing the bigger poop from the bigger fish to be sucked through...

Maybe it is getting too crowded in the tank... 1000L tank with 48 trouts...

Hi Ivan,
my system is still cycling up (running well though) but I have had the same problem lately with dropping PH. The trout - 25 in 1000l FT stop feeding when the ph is getting low. I used about 1.5 cups of garden lim to raise the ph to around 6.8 and then the feeding started again. I read here somewhere that trout can handle as low as 4.5PH which is good but they sure let you know when they are not happy. My tshirt filter failed - the cotton ripped with the weight of the water after perishing so there was no solids filtration. I think this is the reason my ph dropped as the solids suddenly were all through the system? May be a coincidence but sounds the same as your scenario. Anyway, PH at 6.8 now and all seems ok. I also hung a bag of shell grit in the sump tank that will hopefully buffer fo rthis sort of thing....I dont think thats crowded btw - i'm hoping to double the number in the 1000lt when cycled in and running...

My pH has dropped below 6 as I have written many times and have no feed problems, in my opinion throwing things in the water to change things quickly does more harm than good, is written here approaching rain or barometric pressure drop can put fish off feed for a day or 2, I haven't experienced it (approaching rain that is ) but others have, I put shell grit into the system and it has raised pH very slowly to just over 6 now, trout are feeding like piranha's and always have

Oh well, thanks for the replies. They are feeding again. I had a bag of shell grit in the tank but I noticed solids gathering so I removed it. Will have to make a more permanent suspended method of introducing shell grit.

I think the barometric pressure drop has some truth to it and to a certain extent may be the pH and built-up solids as well. The days the trouts went off the feed, the trouts in other system (with higher pH and less solid built-up) fed well.

Although it could be dissolved O2 as well, as I usually switch my pump to manual when the fishes are acting weird. Just a precaution. Electricity is cheap compared to the stress (both fishes and fish-owners). Will need to check the air-hose out. I think they are not giving good aeration anymore. Considering switching back to airstones.

So once I get my third system cycled, I need to rethink the design of the first system. Bigger pump, with a venturi bypass directed to the bottom of the tank to blow shit up... Shell grit... a couple of extra features... of course once the trouts are transferred to the third system.

Hi all, my trout have gone off the feed in the last few days but I think it may be down to the excessive rain we have had over the last few days. Sorry but I do not have any parameters to report I will have some up tomorrow. Is this some thing that others have experienced in Perth in the last few days.

Well no, my trouts continued to "hammer" the feed for the last few days... I do have a funny feeling that my trouts actually went off their feed because of aeration. The airhose I have in my tank was really clogging up, hence I replaced it with a new airstone. After I have done that, the trouts have been feeding regularly... but it is still a guess at the moment.

Sounds like it's dinner time

yep my trout didn't feed last 2 mornings but are hitting it hard in the afternoon

Nah...not yet... I am actually going to upgrade my aeration but introducing a separate water pump with venturi... Acts to add air and the water will blow across the tank bottom so will help suspend the crap and let it get sucked out during the normal pumping cycle.