Overstocking?

[Wanderer]

K, so many of you may already know my background story regarding how I came to keep a couple of large groups of Garra Rufa fish.

I am just posting this thread to ask about overstocking. Maybe some of you have more experience or knowledge on this than I do.

If you are technically "overstocked", is it possible that regular water changes and good products like Seachem Prime will counteract any negative effects caused by the overstocking?

My fish seem otherwise happy enough to live in a large group. They aren't aggressive toward each other, even when they go into a "feeding frenzy" over their daily morning algae wafers. When they are resting they sort of form little groups together at the bottom of the tank.

I have already managed to rehome some but I am wondering if it is really necessary for me to rehome many more if I can find a way to keep them healthy and if the filter will mature to a point where it can handle the waste anyway?

http/www.fishforums.net/index.php?/topic/404407-worried-some-of-my-garra-rufa-fish-may-be-sick/page__pid__3404708#entry3404708

 

[N0body Of The Goat]

The issue in your tank is not so much aggression, but ensuring every fish gets sufficient food, which in turn means you need proportionally way more bacteria than a typical setup to detoxify the resultant ammonia and nitrite. However, while nitrate is not toxic to many hobby fish in low-moderate concentrations, fish are believed to keel over when nitrate exceeds 300mg/l.

Nitrate is removed by water changes, the rate of nitrate reduction will depend upon the replacement water, for example "reverse osmosis" has zero nitr\te in it while my tap water comes with 40-50mg/l. But here comes the fun bit, typical nitrate test kits in the hobby are positively awful (even liquid ones), so how are you going to know how much nitrate really is in the water and therfor how much you need to change in order to make it safe for the overstocked fish?

 

[Wanderer]

Basically I have a twin tanks, approximately 90 litres each, big filter at the back in a separate part including a UV filter.

In one tank I have 21 garra rufa fish. In another I have 46.

They range from 1-2 inches. A couple in each tank are 3 inches.

There are 7 Marimo Balls in each tank. I'm getting 11 more soon.

Going to add some Java Fern and Java Moss.

I do 12% water changes from each tank daily.

I have been using Stress Zyme, Stress Coat and Ammo Lock, but going to switch to Seachem Prime.

The issue in your tank is not so much aggression, but ensuring every fish gets sufficient food, which in turn means you need proportionally way more bacteria than a typical setup to detoxify the resultant ammonia and nitrite. However, while nitrate is not toxic to many hobby fish in low-moderate concentrations, fish are believed to keel over when nitrate exceeds 300mg/l.

Nitrate is removed by water changes, the rate of nitrate reduction will depend upon the replacement water, for example "reverse osmosis" has zero nitr\te in it while my tap water comes with 40-50mg/l. But here comes the fun bit, typical nitrate test kits in the hobby are positively awful (even liquid ones), so how are you going to know how much nitrate really is in the water and therfor how much you need to change in order to make it safe for the overstocked fish?

Good question.

Maybe I should be doing more than 12% changes?

 

[fluttermoth]

First of all, I would swap some fish, so you have a more equal number in each tank.

Although, as NOTG says, nitrate tests are very inaccurate, it would at least give you a ball park figure to work with; especially useful if you test your tap water as well.

You might find that larger, less frequent changes are better for your fish; mathematically they are.

 

[Wanderer]

I'm not sure if the filters in the garra rufa spa systems are a bit different to standard filters. It says recommends here to keep 65 fish per tank:

http/www.garrafishsystems.com/testimonial-faqs.html

My tank wasn't from this supplier (I couldn't afford to buy one new lol)....however it is very similar to the one I saw at the place I got my fish from.

I will take some pictures of the filter later and post it.

Here is more info:

http/princefish.com/garra_rufa_doctor_fish_drawings_construction.html

Perhaps I should email some experts on garra rufa spa systems to ask them about this.

 

[Wanderer]

First of all, I would swap some fish, so you have a more equal number in each tank.

Although, as NOTG says, nitrate tests are very inaccurate, it would at least give you a ball park figure to work with; especially useful if you test your tap water as well.

You might find that larger, less frequent changes are better for your fish; mathematically they are.

I know. I just don't like disturbing them/ stressing them.

When I went a couple of days without changing the water, the ammonia levels sky rocketed; I dare not do it again. The smaller changes are much easier for me as I have to carry buckets of water up and down stairs. I read that smaller changes can be best in the aspect of matching the water chemistry of the new water and tank. I know my tap water will be more often than not the same, but who knows if one day it might change.

Hopefully the filters will mature more.